The following is speculation. I have a low level of confidence that if what follows is indeed the case, those responsible for our security would fully disclose the potential risks in order to prepare for worst case mitigation.
The satellite causing all the excitement I believe to be a "Radar Imaging Satellite." This means that it has the capability to use high resolution radar to image instead of using CCDs or powerful cameras.
In the past, some "Radar Imaging Satellites" have used RTGs and Reactors to power the radars because of the size and associated problems related to solar arrays for high power applications.
A RTG is a thermocouple device that uses non-fissile decay of a radioactive nuclide to generate heat that is then converted through the use of a thermocouple to generate electrical power. These devices can be fueled by various types of radio-nuclides to include, but are not limited to, isotopes of 235, 238, 239, or 210.
I am not familiar with the reactor designs used in space applications but conjecture leads me to believe that instead of non-fissile decay, a moderated fissile material is used to generate heat. The significantly higher operating temperature could then be used with thermocouples, or closed loop working fluid generator systems, to produce electrical power. In the case of both the thermocouple and "heat engine" the higher the operating temperature (actually the thermal gradient through which the process operates) defines the base efficiency. In the case of the heat engine this is known as the Carnot Cycle Efficiency, but in both cases encourages the highest possible operating temperatures.
I believe these types of power generation systems could contain anywhere from a few pounds of radio nuclides up to 10s or even hundreds of pounds of material depending on scale.
I consider both RTG and Space Reactor technologies as "mature."
This particular satellite never established initial on orbit radio communication. What this means is, in the case of an accident or normal decay re-entry, the commands to separate the power pack, if it has one on board (which I have no evidence other than the obvious), could not be made to separate the power pack from the satellite as is normally done with RTGs at the life cycle end. The RTG or other type of power pack is then allowed to burn up or is boosted to a burial orbit. This is my understanding (or misunderstanding) of how things were to have supposed to work in the past.
Radio Nuclides may also be used as heaters to maintain constant or minimum temperatures in some applications and one satellite may have anywhere from a couple to a couple dozen small heating devices on board depending on sub-systems needs. These types of devices would contain from less than a gram to few grams of material each. Expected materials used would include isotopes of plutonium or other suitable radio nuclide materials.
The reasons I suspect that this satellite may have nuclear materials on board for use in power production or sub-system heaters are:
1. Past precedence.
2. The power required for "Radar Imaging."
3. The fact that these obvious questions and concerns have not been raised.
Regarding the stated concern for the "Hydrazine"; it is a "propellant" used for attitude control and orbital maintenance and maneuvering. It is not nice stuff but I don't think a half a ton of hydrazine would cause this much excitement.
Gavilan
A while back, (as a joke) I had started a thread about this satellite.
http://forum.physorg.com/index.php?showtopic=20174&hl=
I didn't take off but, as the time gets closer I'm sure there will be more interest in this topic. Wouldn't surprise me to see some parts show up on Ebay (Ha, ha).
You said:
>but I don't think a half a ton of hydrazine would cause this much excitement.
I'm sure the buzz is more for the technology falling into the wrong hands than for public safety.
http://forum.physorg.com/index.php?showtopic=20174&hl=
I didn't take off but, as the time gets closer I'm sure there will be more interest in this topic. Wouldn't surprise me to see some parts show up on Ebay (Ha, ha).
You said:
>but I don't think a half a ton of hydrazine would cause this much excitement.
I'm sure the buzz is more for the technology falling into the wrong hands than for public safety.
QUOTE (paul h+Feb 16 2008, 08:23 AM)
>but I don't think a half a ton of hydrazine would cause this much excitement.
I'm sure the buzz is more for the technology falling into the wrong hands than for public safety.
The hydrazine is now frozen and it could very well make it to the earth pretty much intact (as did the hydrazine tank on the Columbia).
It is a SERIOUS hazard as in worse case it could contaminate a fairly large populated area (city blocks) with very hazardous levels of Hydrazine.
http://www.pcl.ox.ac.uk/MSDS/HY/hydrazine.html
The technology on the other hand would not likely arrive in a state that is meaningful to anyone.
As to the RTGs. The are designed to withstand re-entry at orbital speeds without being breached.
RTG design changed after the 1964 the Transit 5BN navigational satellite reentered the atmosphere and the RTG burned up in the atmosphere distributing Pu globally.
In contrast, the subsequently redesigned RTGs have re-entered the atmosphere and since the radioactive material is now contained in an outer shield and is itself formed into a high temperature ceramic, the RTGs are able to maintain their integrity.
A recent example was the re-entry of the Nimbus B-1 satellite. There was no release of radioactivity and the radioactive material was recovered (and reused).
Arthur
I'm sure the buzz is more for the technology falling into the wrong hands than for public safety.
The hydrazine is now frozen and it could very well make it to the earth pretty much intact (as did the hydrazine tank on the Columbia).
It is a SERIOUS hazard as in worse case it could contaminate a fairly large populated area (city blocks) with very hazardous levels of Hydrazine.
http://www.pcl.ox.ac.uk/MSDS/HY/hydrazine.html
QUOTE
Harmful if inhaled or swallowed. Poison. Probable human carcinogen. Readily absorbed through the skin. May cause severe skin and eye irritation or burns. Long-term exposure may cause CNS, lungs, blood, liver and kidney damage. Typical TLV/TWA 0.1 ppm. Typical STEL 1 ppm.
The technology on the other hand would not likely arrive in a state that is meaningful to anyone.
As to the RTGs. The are designed to withstand re-entry at orbital speeds without being breached.
RTG design changed after the 1964 the Transit 5BN navigational satellite reentered the atmosphere and the RTG burned up in the atmosphere distributing Pu globally.
In contrast, the subsequently redesigned RTGs have re-entered the atmosphere and since the radioactive material is now contained in an outer shield and is itself formed into a high temperature ceramic, the RTGs are able to maintain their integrity.
A recent example was the re-entry of the Nimbus B-1 satellite. There was no release of radioactivity and the radioactive material was recovered (and reused).
Arthur
Hi everybody!
Many radar satellites work on solar panels. In fact, the radar antenna is much bigger than solar panels. I see no good reason to use an RTG or a nuclear reactor on such a satellite. As far as I know, no Earth-orbiting satellite use them, neither civilian nor military, since solar light is plentiful here. Only spacecrafts designed to reach the outer Solar system rely on them.
Destroying an RTG would make it more dangerous. A reactor as well.
Radar satellites aren't very good for spying purposes, because their resolution is so bad. More power won't improve it.
Hydrazine is a big concern indeed. Worse, it could probably be MMH or UDMH (CH3CH3NNH) which are often called imprecisely "hydrazine" but are about 1000 times as unhealthy: Carcinogens with allowable levels of 1ppb rather than 1ppm. Having 100kg of them nearby certainly is an uneasy thought. On the other hand, spreading it in the atmosphere should allow it to burn before it reaches us. I don't see why it should be frozen, but its tank may perfectly survive the reentry. Satellites evaporating through reentry is just an old myth.
Nobody imagines this satellite to be a weapon? You all speak of a spy satellite...
Another explanation I heard is that the US military wants to test or to demonstrate its antisatellite capability and exaggerates the risk posed by this satellite to overcome some international agreements. Credible.
Many radar satellites work on solar panels. In fact, the radar antenna is much bigger than solar panels. I see no good reason to use an RTG or a nuclear reactor on such a satellite. As far as I know, no Earth-orbiting satellite use them, neither civilian nor military, since solar light is plentiful here. Only spacecrafts designed to reach the outer Solar system rely on them.
Destroying an RTG would make it more dangerous. A reactor as well.
Radar satellites aren't very good for spying purposes, because their resolution is so bad. More power won't improve it.
Hydrazine is a big concern indeed. Worse, it could probably be MMH or UDMH (CH3CH3NNH) which are often called imprecisely "hydrazine" but are about 1000 times as unhealthy: Carcinogens with allowable levels of 1ppb rather than 1ppm. Having 100kg of them nearby certainly is an uneasy thought. On the other hand, spreading it in the atmosphere should allow it to burn before it reaches us. I don't see why it should be frozen, but its tank may perfectly survive the reentry. Satellites evaporating through reentry is just an old myth.
Nobody imagines this satellite to be a weapon? You all speak of a spy satellite...
Another explanation I heard is that the US military wants to test or to demonstrate its antisatellite capability and exaggerates the risk posed by this satellite to overcome some international agreements. Credible.
Thanks for beginning this thread, I will be reading with interest. I wanted to begin one yesterday on this topic but had no knowledge of the subject, so didn't. 
QUOTE (Enthalpy+Feb 16 2008, 01:03 PM)
I don't see why it should be frozen, but its tank may perfectly survive the reentry.
Because it hasn't been able to keep its solar panels oriented to produce the power needed to keep the tank warm.
I agree with you about there not being RTGs on board this craft, my last post was just to point out, that even if there were, the modern RTGs wouldn't pose a re-entry hazard.
Arthur
Because it hasn't been able to keep its solar panels oriented to produce the power needed to keep the tank warm.
I agree with you about there not being RTGs on board this craft, my last post was just to point out, that even if there were, the modern RTGs wouldn't pose a re-entry hazard.
Arthur
On CNN yesterday they said that this thing didn't have solar cells so it would be harder to find
QUOTE (paul h+Feb 16 2008, 05:23 PM)
On CNN yesterday they said that this thing didn't have solar cells so it would be harder to find
I think they meant that they didn't deploy as the spacecraft failed about the same time it reached orbit.
Arthur
I think they meant that they didn't deploy as the spacecraft failed about the same time it reached orbit.
Arthur
Oh come on CNN is never wrong,,,,,, 
(strike that)
Edit: I did find that adoucette is correct (again)
http://www.globalsecurity.org/space/systems/e-305.htm
Quote from site"
>Soon after launch John Locker in the UK reported that the NROL-21 satellite failed within hours of its launch and the solar arrays never deployed.
So much for CNN
(strike that)
Edit: I did find that adoucette is correct (again)
http://www.globalsecurity.org/space/systems/e-305.htm
Quote from site"
>Soon after launch John Locker in the UK reported that the NROL-21 satellite failed within hours of its launch and the solar arrays never deployed.
So much for CNN
Anyone who has already talked to media and listened to what comes on the air from what he said becomes very cautious when he hears information... However, CNN is certainly not the worst one round here. It's even among the very best ones, I say.
Freezing: It depends on how the satellite is designed. Most of them are made to keep the batteries between -5°C and +15°C without any electrical heating, by choosing properly the materials and colours of the outer surfaces. Under such conditions, MMH (-52°C!) and UDMH (-57°C!) are far from freezing, while N2H4 may (+1°C). As satellites use a bipropellant (that is, combustion with N2O4, instead of catalytic decomposition of N2H4), my bet is that they chose an MMH-UDMH mixture known as Aerozine.
Freezing: It depends on how the satellite is designed. Most of them are made to keep the batteries between -5°C and +15°C without any electrical heating, by choosing properly the materials and colours of the outer surfaces. Under such conditions, MMH (-52°C!) and UDMH (-57°C!) are far from freezing, while N2H4 may (+1°C). As satellites use a bipropellant (that is, combustion with N2O4, instead of catalytic decomposition of N2H4), my bet is that they chose an MMH-UDMH mixture known as Aerozine.
The Russian government happens to express the same opinion:
http://news.bbc.co.uk/2/hi/americas/7248995.stm
http://news.bbc.co.uk/2/hi/americas/7248995.stm
QUOTE (Enthalpy+Feb 16 2008, 09:06 PM)
The Russian government happens to express the same opinion:
http://news.bbc.co.uk/2/hi/americas/7248995.stm
Just Propaganda.
If we wanted to test taking out a satellite in orbit we would set up a REALISTIC ORBITAL test.
Waiting till the satellite is just about to de-orbit makes it pretty clear that there is no ulterior motive as the profile is then pretty much the same as a traditional ballistic missile.
And that's what the Standard 3 missile was built and tested to take out.
http://www.globalsecurity.org/space/systems/sm3.htm
$40 million to avoid possibly poisoning the people in several blocks of Sydney (or LA or Beijing or wherever) is a small price to pay.
Of course Paranoid types will try to make it into something sinister.
Arthur
http://news.bbc.co.uk/2/hi/americas/7248995.stm
Just Propaganda.
If we wanted to test taking out a satellite in orbit we would set up a REALISTIC ORBITAL test.
Waiting till the satellite is just about to de-orbit makes it pretty clear that there is no ulterior motive as the profile is then pretty much the same as a traditional ballistic missile.
And that's what the Standard 3 missile was built and tested to take out.
http://www.globalsecurity.org/space/systems/sm3.htm
$40 million to avoid possibly poisoning the people in several blocks of Sydney (or LA or Beijing or wherever) is a small price to pay.
Of course Paranoid types will try to make it into something sinister.
Arthur
Found this update with good details of hit or miss scenarios.
U.S. to Attempt to Shoot Down Faulty Satellite
quote:
(The ramifications of the operation are diplomatic, as well as military and scientific, in part because the United States criticized China last year when Beijing tested an anti satellite system with an old weather satellite.)
shoot to kill
U.S. to Attempt to Shoot Down Faulty Satellite
quote:
(The ramifications of the operation are diplomatic, as well as military and scientific, in part because the United States criticized China last year when Beijing tested an anti satellite system with an old weather satellite.)
shoot to kill
First off, thanks for your replies.
Aviation Week has stated: “The satellite is not nuclear-powered so there should be no risk from radioactive materials, although some spacecraft do carry tiny plutonium-powered heaters, but these would not pose a debris hazard.”
http://www.aviationweek.com/aw/generic/sto.../aw020408p2.xml
End quote.
The above is single source; I have been unable to find any other source that addresses this issue.
I assume that aviation week would not risk a loss in credibility unless there was a high level of confidence in the above statement. How the satellite is powered may be different than how the Radars are powered; but I will accept Aviation Week’s inference that there are no isotopes on board used for primary power production. I also believe that any information as to a nuclear power source for powering the radars would be “classified” information. I have not seen this issue addressed in public disclosure by government sources. This causes me some concern.
Regarding that part of the quote referencing “tiny plutonium powered heaters: These heaters would probably be powered by the 86 year half life plutonium isotope. This isotope is extremely hazardous if inhaled or ingested. Even the small amounts in each heater unit would pose significant contamination risk. Although wide dispersal by re-entry burn up would prevent any significant or even measurable increases in background radiation levels, these nuclides would still pose a significant risk if inhaled or ingested. I do not know how oxidation with atmospheric gasses during the re-entry burn up might affect the carcinogenic properties, but in this regard the nuclides of this isotope would be several orders of magnitude more dangerous than the longest half life isotope.
Reactors should not be confused with RTGs. A quick internet search should convince the reader that the planning and design of space reactors for use in earth orbiting radar and weapons applications has been on going for well over 20 years. An example is the SP-100 reactor. I believe it can be safely assumed that there are more advanced designs either in development and most probably, application.
In regards to the recovery of the Nimbus B RTG:
Nimbus B never achieved closed orbital energy and cannot be used as an example of RTG survivability. This can be seen by referencing
http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=NIMBS-B
There have been several publicly disclosed, discovered, or claimed failures of RTG containment upon re-entry; the Peru incident possibly being the most recent.
Another interesting quote from Aviation Week: “The radars can differentiate camouflaged trucks or pack animals in mountainous terrain or under trees. They can also see just fine at night and through clouds. ------Contrary to media reports that say the spacecraft is as large as a school bus weighing up to 20,000 lb., the failed satellite is actually one of the smallest launched in the last several years by the NRO.”
Gavilan
Aviation Week has stated: “The satellite is not nuclear-powered so there should be no risk from radioactive materials, although some spacecraft do carry tiny plutonium-powered heaters, but these would not pose a debris hazard.”
http://www.aviationweek.com/aw/generic/sto.../aw020408p2.xml
End quote.
The above is single source; I have been unable to find any other source that addresses this issue.
I assume that aviation week would not risk a loss in credibility unless there was a high level of confidence in the above statement. How the satellite is powered may be different than how the Radars are powered; but I will accept Aviation Week’s inference that there are no isotopes on board used for primary power production. I also believe that any information as to a nuclear power source for powering the radars would be “classified” information. I have not seen this issue addressed in public disclosure by government sources. This causes me some concern.
Regarding that part of the quote referencing “tiny plutonium powered heaters: These heaters would probably be powered by the 86 year half life plutonium isotope. This isotope is extremely hazardous if inhaled or ingested. Even the small amounts in each heater unit would pose significant contamination risk. Although wide dispersal by re-entry burn up would prevent any significant or even measurable increases in background radiation levels, these nuclides would still pose a significant risk if inhaled or ingested. I do not know how oxidation with atmospheric gasses during the re-entry burn up might affect the carcinogenic properties, but in this regard the nuclides of this isotope would be several orders of magnitude more dangerous than the longest half life isotope.
Reactors should not be confused with RTGs. A quick internet search should convince the reader that the planning and design of space reactors for use in earth orbiting radar and weapons applications has been on going for well over 20 years. An example is the SP-100 reactor. I believe it can be safely assumed that there are more advanced designs either in development and most probably, application.
In regards to the recovery of the Nimbus B RTG:
Nimbus B never achieved closed orbital energy and cannot be used as an example of RTG survivability. This can be seen by referencing
http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=NIMBS-B
There have been several publicly disclosed, discovered, or claimed failures of RTG containment upon re-entry; the Peru incident possibly being the most recent.
Another interesting quote from Aviation Week: “The radars can differentiate camouflaged trucks or pack animals in mountainous terrain or under trees. They can also see just fine at night and through clouds. ------Contrary to media reports that say the spacecraft is as large as a school bus weighing up to 20,000 lb., the failed satellite is actually one of the smallest launched in the last several years by the NRO.”
Gavilan
http://news.yahoo.com/s/nm/20080217/ts_nm/...nHJ_lUkJ70E1vAI
Quote from site:
>"Relevant departments in China are closely watching the situation and studying preventive measures," Liu said in a brief statement posted on the Foreign Ministry's Web site (www.fmprc.gov.cn).
>On Saturday, Russia's Defense Ministry said the U.S. plan could be used as a cover to test a new space weapon.
(to test a new space weapon). hummmm
naw we'd never do that.
Quote from site:
>"Relevant departments in China are closely watching the situation and studying preventive measures," Liu said in a brief statement posted on the Foreign Ministry's Web site (www.fmprc.gov.cn).
>On Saturday, Russia's Defense Ministry said the U.S. plan could be used as a cover to test a new space weapon.
(to test a new space weapon).
hummmmnaw we'd never do that.
QUOTE (Gavilan+Feb 17 2008, 11:34 AM)
First off, thanks for your replies.
Aviation Week has stated: “The satellite is not nuclear-powered so there should be no risk from radioactive materials, although some spacecraft do carry tiny plutonium-powered heaters, but these would not pose a debris hazard.”
http://www.aviationweek.com/aw/generic/sto.../aw020408p2.xml
End quote.
The above is single source; I have been unable to find any other source that addresses this issue.
I assume that aviation week would not risk a loss in credibility unless there was a high level of confidence in the above statement. How the satellite is powered may be different than how the Radars are powered; but I will accept Aviation Week’s inference that there are no isotopes on board used for primary power production. I also believe that any information as to a nuclear power source for powering the radars would be “classified” information. I have not seen this issue addressed in public disclosure by government sources. This causes me some concern.
Regarding that part of the quote referencing “tiny plutonium powered heaters: These heaters would probably be powered by the 86 year half life plutonium isotope. This isotope is extremely hazardous if inhaled or ingested. Even the small amounts in each heater unit would pose significant contamination risk. Although wide dispersal by re-entry burn up would prevent any significant or even measurable increases in background radiation levels, these nuclides would still pose a significant risk if inhaled or ingested. I do not know how oxidation with atmospheric gasses during the re-entry burn up might affect the carcinogenic properties, but in this regard the nuclides of this isotope would be several orders of magnitude more dangerous than the longest half life isotope.
Reactors should not be confused with RTGs. A quick internet search should convince the reader that the planning and design of space reactors for use in earth orbiting radar and weapons applications has been on going for well over 20 years. An example is the SP-100 reactor. I believe it can be safely assumed that there are more advanced designs either in development and most probably, application.
In regards to the recovery of the Nimbus B RTG:
Nimbus B never achieved closed orbital energy and cannot be used as an example of RTG survivability. This can be seen by referencing
http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=NIMBS-B
There have been several publicly disclosed, discovered, or claimed failures of RTG containment upon re-entry; the Peru incident possibly being the most recent.
Another interesting quote from Aviation Week: “The radars can differentiate camouflaged trucks or pack animals in mountainous terrain or under trees. They can also see just fine at night and through clouds. ------Contrary to media reports that say the spacecraft is as large as a school bus weighing up to 20,000 lb., the failed satellite is actually one of the smallest launched in the last several years by the NRO.”
Gavilan
There is NO NEED for an RTG for an earth orbiting satellite.
There is no reason to believe that there was one on board this satellite.
As far as reentry, the RTGs were DESIGNED to survive the entire range of postulated accidents including launch vehicle explosion or fire, reentry into the atmosphere followed by land or water impact.
An outer covering of graphite provides protection against the structural, thermal, and eroding environments of a potential reentry while additional graphite components provide impact protection.
Finally, an iridium cladding of the actual fuel cells provides post-impact containment.
Then there is the fuel itself, the fuel is in the form of plutonium-238 dioxide, a ceramic material which is resistant to fracturing.
What Peru Incident are you talking about?
As to reactors, they are being studied to support LUNAR AND MARS bases.
Their output (at the smallest sizes) is FAR greater than a satellite could possibly use and their weight is no small issue.
And as your article points out
So to suggest that it MIGHT have a friggin reactor on board and that "This causes me some concern" is simply being OVERLY paranoid.
Arthur
Aviation Week has stated: “The satellite is not nuclear-powered so there should be no risk from radioactive materials, although some spacecraft do carry tiny plutonium-powered heaters, but these would not pose a debris hazard.”
http://www.aviationweek.com/aw/generic/sto.../aw020408p2.xml
End quote.
The above is single source; I have been unable to find any other source that addresses this issue.
I assume that aviation week would not risk a loss in credibility unless there was a high level of confidence in the above statement. How the satellite is powered may be different than how the Radars are powered; but I will accept Aviation Week’s inference that there are no isotopes on board used for primary power production. I also believe that any information as to a nuclear power source for powering the radars would be “classified” information. I have not seen this issue addressed in public disclosure by government sources. This causes me some concern.
Regarding that part of the quote referencing “tiny plutonium powered heaters: These heaters would probably be powered by the 86 year half life plutonium isotope. This isotope is extremely hazardous if inhaled or ingested. Even the small amounts in each heater unit would pose significant contamination risk. Although wide dispersal by re-entry burn up would prevent any significant or even measurable increases in background radiation levels, these nuclides would still pose a significant risk if inhaled or ingested. I do not know how oxidation with atmospheric gasses during the re-entry burn up might affect the carcinogenic properties, but in this regard the nuclides of this isotope would be several orders of magnitude more dangerous than the longest half life isotope.
Reactors should not be confused with RTGs. A quick internet search should convince the reader that the planning and design of space reactors for use in earth orbiting radar and weapons applications has been on going for well over 20 years. An example is the SP-100 reactor. I believe it can be safely assumed that there are more advanced designs either in development and most probably, application.
In regards to the recovery of the Nimbus B RTG:
Nimbus B never achieved closed orbital energy and cannot be used as an example of RTG survivability. This can be seen by referencing
http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=NIMBS-B
There have been several publicly disclosed, discovered, or claimed failures of RTG containment upon re-entry; the Peru incident possibly being the most recent.
Another interesting quote from Aviation Week: “The radars can differentiate camouflaged trucks or pack animals in mountainous terrain or under trees. They can also see just fine at night and through clouds. ------Contrary to media reports that say the spacecraft is as large as a school bus weighing up to 20,000 lb., the failed satellite is actually one of the smallest launched in the last several years by the NRO.”
Gavilan
There is NO NEED for an RTG for an earth orbiting satellite.
There is no reason to believe that there was one on board this satellite.
As far as reentry, the RTGs were DESIGNED to survive the entire range of postulated accidents including launch vehicle explosion or fire, reentry into the atmosphere followed by land or water impact.
An outer covering of graphite provides protection against the structural, thermal, and eroding environments of a potential reentry while additional graphite components provide impact protection.
Finally, an iridium cladding of the actual fuel cells provides post-impact containment.
Then there is the fuel itself, the fuel is in the form of plutonium-238 dioxide, a ceramic material which is resistant to fracturing.
What Peru Incident are you talking about?
As to reactors, they are being studied to support LUNAR AND MARS bases.
Their output (at the smallest sizes) is FAR greater than a satellite could possibly use and their weight is no small issue.
And as your article points out
QUOTE
Contrary to media reports that say the spacecraft is as large as a school bus weighing up to 20,000 lb., the failed satellite is actually one of the smallest launched in the last several years by the NRO.
So to suggest that it MIGHT have a friggin reactor on board and that "This causes me some concern" is simply being OVERLY paranoid.
Arthur
QUOTE (Gavilan+Feb 17 2008, 04:34 PM)
There have been several publicly disclosed, discovered, or claimed failures of RTG containment upon re-entry; the Peru incident possibly being the most recent.
A crater created by a stony meteorite doesn't help your case in the slightest.
http://www.livinginperu.com/news-5223-peru...l-heritage-site
A crater created by a stony meteorite doesn't help your case in the slightest.
http://www.livinginperu.com/news-5223-peru...l-heritage-site
There are several radar-equipped satellites in orbit around Mars and despite the fact that sunlight at Mars is less then half as intense as at Earth, they still use solar panels. RTGs are not necessary for this sort of application.
How feasible is it that we will be able to hit the target, when attempting to shoot it down?
QUOTE (tikay+Feb 17 2008, 02:11 PM)
How feasible is it that we will be able to hit the target, when attempting to shoot it down?
I assume it will be VERY feasible.
The rocket that we are using, was designed for this capability.
See: http://www.globalsecurity.org/space/systems/sm3.htm
Arthur
I assume it will be VERY feasible.
The rocket that we are using, was designed for this capability.
See: http://www.globalsecurity.org/space/systems/sm3.htm
Arthur
In case anyone wants to track the satellite
http://www.heavens-above.com/orbitdisplay.asp?satid=29651
This will tell you when there is even a slight chance that you might want to take cover if you are overly paranoid about being hit by falling space debris.
The satellite makes one revolution every 90 minutes, and of course the Earth is rotating under the orbital path, so the orbital track will move westward about 500 miles (at the mid latitudes where most of us live) each revolution.
Those in any danger at all would be under the approx oribital path for approx 1/3 revolution ahead of where the satellite is at any given moment (adjust based on level of paranoia).
Arthur
http://www.heavens-above.com/orbitdisplay.asp?satid=29651
This will tell you when there is even a slight chance that you might want to take cover if you are overly paranoid about being hit by falling space debris.
The satellite makes one revolution every 90 minutes, and of course the Earth is rotating under the orbital path, so the orbital track will move westward about 500 miles (at the mid latitudes where most of us live) each revolution.
Those in any danger at all would be under the approx oribital path for approx 1/3 revolution ahead of where the satellite is at any given moment (adjust based on level of paranoia).
Arthur
QUOTE (adoucette+Feb 17 2008, 05:12 PM)
There is NO NEED for an RTG for an earth orbiting satellite.
There is no reason to believe that there was one on board this satellite.
As far as reentry, the RTGs were DESIGNED to survive the entire range of postulated accidents including launch vehicle explosion or fire, reentry into the atmosphere followed by land or water impact.
An outer covering of graphite provides protection against the structural, thermal, and eroding environments of a potential reentry while additional graphite components provide impact protection.
Finally, an iridium cladding of the actual fuel cells provides post-impact containment.
Then there is the fuel itself, the fuel is in the form of plutonium-238 dioxide, a ceramic material which is resistant to fracturing.
What Peru Incident are you talking about?
As to reactors, they are being studied to support LUNAR AND MARS bases.
Their output (at the smallest sizes) is FAR greater than a satellite could possibly use and their weight is no small issue.
And as your article points out
So to suggest that it MIGHT have a friggin reactor on board and that "This causes me some concern" is simply being OVERLY paranoid.
Arthur
Arthur,
Thank you for your concern that I am being overly "paranoid" in regards to the use of Reactors (not RTGs, they don't produce enough power) in Radar Imaging Satellites.
Your level of faith in your beliefs is quite commendable; but past precedence, the solar constant, efficiency of solar arrays, observability, and problems associated with solar arrays in high power applications bring that faith in conflict with both physics and history.
I don't think the fact that these devices, which have in the past and are currently being used in earth orbit, is a matter of debate. They have, they are, and the plans for the future include scales which are orders of magnitude greater that what I KNOW have been used in earth orbit in the past.
The debate is whether this specific satellite uses a reactor as its primary power source for the radars.
What do you estimate the power required for Radar Imaging of a "truck" from 300 miles? What would the total solar area have to be at a stupendous 25 percent efficiency of a solar array to power that radar? At an orbital inclination of about 54 degrees in a circular orbital radius of about 300 miles would the arrays have continuous exposure to solar insolation?
If past precedence and my understanding of the state and direction of the technology tends to make me a bit paranoid then so be it. In the specific regard of nuclear power being used in earth orbit applications; the paranoia that you attach to my interests describe a status quo that is quite closer to the reality than your interpretation of the same.
Perhaps a closer study of the issue would be a stronger support of your arguments than personally attacking my interest as "overly paranoid."
Here is a little background on the approximate 20 or so I am aware of.
Granted, this is single source but I have many more as I have been interested in and studied this issue for about 30 years.
http://www.daviddarling.info/encyclopedia/R/RORSAT.html
Soviet naval reconnaissance satellites often launched to coincide with major NATO and American navy maneuvers. A characteristic feature of RORSATs was their large radar antennas used to bounce signals off the ocean in order to locate ships. The strength of the signals required for this to work effectively, combined with the relatively backward state of electronics technology in the Eastern bloc, forced Soviet designers to adopt a radical solution – the use of a small nuclear reactor to power the RORSAT radar (see nuclear power for spacecraft).
Although prototype RORSATSs in the mid-1960s flew with only chemical batteries, their operational counterparts, beginning in the 1970s, carried reactors. This introduced a serious risk of contamination because all the RORSATs reentered after a few weeks or months in orbit. To counter the problem, each RORSAT consisted of three major components: the payload and propulsion section, the reactor, and a disposal stage used to lift the reactor into a higher orbit, with an altitude of 900–1,000 km, at the end of the mission. Thus while the main spacecraft decayed, the reactor continued to circle the Earth. Unfortunately, the lifetime of an object at this altitude is about 600 years, whereas uranium-235 and -238 have a half-life of more than one billion years. This means there is presently, in 1,000 km × 65° orbits, about 940 kg of highly-enriched uranium and a further 15 tons of other radioactive material including tens of thousands of droplets, 0.6–2 cm in diameter, which are the remains of the liquid sodium-potassium used to cool the RORSAT reactors.
There have also been accidents – the worst of them on Jan. 24, 1978, when a RORSAT malfunctioned and crashed within Canada’s Northwest Territory, showering radioactive debris onto the Great Slave Lake and surrounding region.
Size 1.3 m (diameter) × 10 m (length)
Total mass of satellite 3,800 kg
Mass of reactor + disposal stage 1,250 kg
Reactor fuel highly enriched (90%) uranium-235
Fuel mass 31 kg
No. of elements 7
Casing beryllium
There is no reason to believe that there was one on board this satellite.
As far as reentry, the RTGs were DESIGNED to survive the entire range of postulated accidents including launch vehicle explosion or fire, reentry into the atmosphere followed by land or water impact.
An outer covering of graphite provides protection against the structural, thermal, and eroding environments of a potential reentry while additional graphite components provide impact protection.
Finally, an iridium cladding of the actual fuel cells provides post-impact containment.
Then there is the fuel itself, the fuel is in the form of plutonium-238 dioxide, a ceramic material which is resistant to fracturing.
What Peru Incident are you talking about?
As to reactors, they are being studied to support LUNAR AND MARS bases.
Their output (at the smallest sizes) is FAR greater than a satellite could possibly use and their weight is no small issue.
And as your article points out
So to suggest that it MIGHT have a friggin reactor on board and that "This causes me some concern" is simply being OVERLY paranoid.
Arthur
Arthur,
Thank you for your concern that I am being overly "paranoid" in regards to the use of Reactors (not RTGs, they don't produce enough power) in Radar Imaging Satellites.
Your level of faith in your beliefs is quite commendable; but past precedence, the solar constant, efficiency of solar arrays, observability, and problems associated with solar arrays in high power applications bring that faith in conflict with both physics and history.
I don't think the fact that these devices, which have in the past and are currently being used in earth orbit, is a matter of debate. They have, they are, and the plans for the future include scales which are orders of magnitude greater that what I KNOW have been used in earth orbit in the past.
The debate is whether this specific satellite uses a reactor as its primary power source for the radars.
What do you estimate the power required for Radar Imaging of a "truck" from 300 miles? What would the total solar area have to be at a stupendous 25 percent efficiency of a solar array to power that radar? At an orbital inclination of about 54 degrees in a circular orbital radius of about 300 miles would the arrays have continuous exposure to solar insolation?
If past precedence and my understanding of the state and direction of the technology tends to make me a bit paranoid then so be it. In the specific regard of nuclear power being used in earth orbit applications; the paranoia that you attach to my interests describe a status quo that is quite closer to the reality than your interpretation of the same.
Perhaps a closer study of the issue would be a stronger support of your arguments than personally attacking my interest as "overly paranoid."
Here is a little background on the approximate 20 or so I am aware of.
Granted, this is single source but I have many more as I have been interested in and studied this issue for about 30 years.
http://www.daviddarling.info/encyclopedia/R/RORSAT.html
Soviet naval reconnaissance satellites often launched to coincide with major NATO and American navy maneuvers. A characteristic feature of RORSATs was their large radar antennas used to bounce signals off the ocean in order to locate ships. The strength of the signals required for this to work effectively, combined with the relatively backward state of electronics technology in the Eastern bloc, forced Soviet designers to adopt a radical solution – the use of a small nuclear reactor to power the RORSAT radar (see nuclear power for spacecraft).
Although prototype RORSATSs in the mid-1960s flew with only chemical batteries, their operational counterparts, beginning in the 1970s, carried reactors. This introduced a serious risk of contamination because all the RORSATs reentered after a few weeks or months in orbit. To counter the problem, each RORSAT consisted of three major components: the payload and propulsion section, the reactor, and a disposal stage used to lift the reactor into a higher orbit, with an altitude of 900–1,000 km, at the end of the mission. Thus while the main spacecraft decayed, the reactor continued to circle the Earth. Unfortunately, the lifetime of an object at this altitude is about 600 years, whereas uranium-235 and -238 have a half-life of more than one billion years. This means there is presently, in 1,000 km × 65° orbits, about 940 kg of highly-enriched uranium and a further 15 tons of other radioactive material including tens of thousands of droplets, 0.6–2 cm in diameter, which are the remains of the liquid sodium-potassium used to cool the RORSAT reactors.
There have also been accidents – the worst of them on Jan. 24, 1978, when a RORSAT malfunctioned and crashed within Canada’s Northwest Territory, showering radioactive debris onto the Great Slave Lake and surrounding region.
Size 1.3 m (diameter) × 10 m (length)
Total mass of satellite 3,800 kg
Mass of reactor + disposal stage 1,250 kg
Reactor fuel highly enriched (90%) uranium-235
Fuel mass 31 kg
No. of elements 7
Casing beryllium
QUOTE (Gavilan+Feb 20 2008, 02:21 PM)
Thank you for your concern that I am being overly "paranoid" in regards to the use of Reactors
Sorry, but you ARE paranoid.
Although it was a military satellite, it isn't actually built by the military. If it had a nuclear reactor on board then literally HUNDREDS of CIVILIANS (at a minimum) would be aware of it and since its coming down uncontrolled its pretty certain that at least ONE of them would have leaked that kind of juicy info to the press by now.
The other part about building even spy satellites in the US is the basics about the spacecraft invariably DO leak.
Thus:
http://www.globalsecurity.org/space/systems/e-305.htm
Note the large solar arrays.
Note the SMALL launch weight.
Note that a REACTOR is heavy, requires special handling, launch permits, etc all of which are obvious to the many 'space watchers' here in the US.
You just can't keep that sort of thing secret.
Well except to PARANOIDS who, apparently will believe ANYTHING.
Like that bs about the event in Peru.
Arthur
QUOTE (adoucette+Feb 20 2008, 08:57 PM)
Sorry, but you ARE paranoid.
Oh well.
Although it was a military satellite, it isn't actually built by the military.
duhhhh
If it had a nuclear reactor on board then literally HUNDREDS of CIVILIANS (at a minimum) would be aware of it and since its coming down uncontrolled its pretty certain that at least ONE of them would have leaked that kind of juicy info to the press by now.
The other part about building even spy satellites in the US is the basics about the spacecraft invariably DO leak.
Thus:
http://www.globalsecurity.org/space/systems/e-305.htm
Note the large solar arrays.
And this picture is of the cancelled Boeing project or the Lockmart model?
Note the SMALL launch weight.
Note that a REACTOR is heavy, requires special handling, launch permits, etc all of which are obvious to the many 'space watchers' here in the US.
Using the mass of the old Soviet reactor and burial motors the mass fraction would be about .17 of total payload mass as given in your reference. There is plenty of reference to projects that would result in even lower mass fractions dedicated to the power reactor.
You just can't keep that sort of thing secret.
Well except to PARANOIDS who, apparently will believe ANYTHING.
Like that bs about the event in Peru.
Whatever Physicist?
Again, a little more study and a little less personal attack would not hurt your credibility any.
Oh well, paranoid I may well be.
Oh well.
Although it was a military satellite, it isn't actually built by the military.
duhhhh
If it had a nuclear reactor on board then literally HUNDREDS of CIVILIANS (at a minimum) would be aware of it and since its coming down uncontrolled its pretty certain that at least ONE of them would have leaked that kind of juicy info to the press by now.
The other part about building even spy satellites in the US is the basics about the spacecraft invariably DO leak.
Thus:
http://www.globalsecurity.org/space/systems/e-305.htm
Note the large solar arrays.
And this picture is of the cancelled Boeing project or the Lockmart model?
Note the SMALL launch weight.
Note that a REACTOR is heavy, requires special handling, launch permits, etc all of which are obvious to the many 'space watchers' here in the US.
Using the mass of the old Soviet reactor and burial motors the mass fraction would be about .17 of total payload mass as given in your reference. There is plenty of reference to projects that would result in even lower mass fractions dedicated to the power reactor.
You just can't keep that sort of thing secret.
Well except to PARANOIDS who, apparently will believe ANYTHING.
Like that bs about the event in Peru.
Whatever Physicist?
Again, a little more study and a little less personal attack would not hurt your credibility any.
Oh well, paranoid I may well be.
QUOTE (Gavilan+Feb 20 2008, 05:59 PM)
Oh well, paranoid I may well be.
no, Paranoid you are.
Which is why you totally ignored the fact that if this satellite had a nuclear reactor on board that they couldn't keep it a secret.
Oh, and by the way, I was just checking on our Lunar Recon Orbiter, that will be launched later this year: The platform will be three-axis stabilized and power of about 1850 W (end-of-life), giving 800 W average over each orbit, will be provided by a 10.7 square meter solar array and stored in an 80 A-hr Li-ion battery.
Which is more watts than the Snap reactor produced.
Like I said, no reason for a reactor onboard when solar panels/li-ion batteries can easily provide all the watts you need.
Arthur
no, Paranoid you are.
Which is why you totally ignored the fact that if this satellite had a nuclear reactor on board that they couldn't keep it a secret.
Oh, and by the way, I was just checking on our Lunar Recon Orbiter, that will be launched later this year: The platform will be three-axis stabilized and power of about 1850 W (end-of-life), giving 800 W average over each orbit, will be provided by a 10.7 square meter solar array and stored in an 80 A-hr Li-ion battery.
Which is more watts than the Snap reactor produced.
Like I said, no reason for a reactor onboard when solar panels/li-ion batteries can easily provide all the watts you need.
Arthur
I wouldn't be that affirmative that secrets invariably leak. Here some examples of projects involving many people and civilians, of which the public (but not the enemy!) stood long unaware of:
- The NSA. How many building workers, bus drivers, cooks...? "No Such Agency".
- The hydrophones net at the Okhotsk sea. Not really cheap.
- Echelon.
- Mind-reading machines.
- Tempest. Existed in 1976 and probably before. Read it first in 1994 approximately.
- EMP weapons.
However, I agree this satellite has no nuclear reactor, simply because no project leader would see an advantage in having one.
Chances of hitting it: Absolutely excellent. A satellite is a sitting duck, with no manoeuvrability and a highly predictable trajectory as long as it's in space. 200 or 300km distance is nothing special to an appropriate missile. Only the satellite's speed is (much) higher than a plane's speed, but as long as the missile doesn't try to chase the target, it should be a mere question of software bounds and sensors angle-of-vision.
By the way, you don't need a warhead in the missile. At the satellite's speed, a Camembert is enough to destroy it. And the satellite wouldn't plunge in the ocean like a hit warplane: It would break into (many) pieces staying on slightly modified orbits, which would thus enter sooner the denser atmosphere.
- The NSA. How many building workers, bus drivers, cooks...? "No Such Agency".
- The hydrophones net at the Okhotsk sea. Not really cheap.
- Echelon.
- Mind-reading machines.
- Tempest. Existed in 1976 and probably before. Read it first in 1994 approximately.
- EMP weapons.
However, I agree this satellite has no nuclear reactor, simply because no project leader would see an advantage in having one.
Chances of hitting it: Absolutely excellent. A satellite is a sitting duck, with no manoeuvrability and a highly predictable trajectory as long as it's in space. 200 or 300km distance is nothing special to an appropriate missile. Only the satellite's speed is (much) higher than a plane's speed, but as long as the missile doesn't try to chase the target, it should be a mere question of software bounds and sensors angle-of-vision.
By the way, you don't need a warhead in the missile. At the satellite's speed, a Camembert is enough to destroy it. And the satellite wouldn't plunge in the ocean like a hit warplane: It would break into (many) pieces staying on slightly modified orbits, which would thus enter sooner the denser atmosphere.
QUOTE (adoucette+Feb 18 2008, 12:19 PM)
In case anyone wants to track the satellite
http://www.heavens-above.com/orbitdisplay.asp?satid=29651
This will tell you when there is even a slight chance that you might want to take cover if you are overly paranoid about being hit by falling space debris.
The satellite makes one revolution every 90 minutes, and of course the Earth is rotating under the orbital path, so the orbital track will move westward about 500 miles (at the mid latitudes where most of us live) each revolution.
Those in any danger at all would be under the approx oribital path for approx 1/3 revolution ahead of where the satellite is at any given moment (adjust based on level of paranoia).
Arthur
Arthur, thanks for the new-to-me link. I've been using J-Track 3D. This'll be a good addition to my bookmarks.
http://www.heavens-above.com/orbitdisplay.asp?satid=29651
This will tell you when there is even a slight chance that you might want to take cover if you are overly paranoid about being hit by falling space debris.
The satellite makes one revolution every 90 minutes, and of course the Earth is rotating under the orbital path, so the orbital track will move westward about 500 miles (at the mid latitudes where most of us live) each revolution.
Those in any danger at all would be under the approx oribital path for approx 1/3 revolution ahead of where the satellite is at any given moment (adjust based on level of paranoia).
Arthur
Arthur, thanks for the new-to-me link. I've been using J-Track 3D. This'll be a good addition to my bookmarks.
And the really dumb question is:
Now where is the missile going to land?
Man,, If we miss this thing, we'll be laughed right out of the "nucler" missile and yatch club.
Now where is the missile going to land?
Man,, If we miss this thing, we'll be laughed right out of the "nucler" missile and yatch club.
QUOTE (Enthalpy+Feb 20 2008, 06:57 PM)
I wouldn't be that affirmative that secrets invariably leak. Here some examples of projects involving many people and civilians, of which the public (but not the enemy!) stood long unaware of:
- The NSA. How many building workers, bus drivers, cooks...? "No Such Agency".
- The hydrophones net at the Okhotsk sea. Not really cheap.
- Echelon.
- Mind-reading machines.
- Tempest. Existed in 1976 and probably before. Read it first in 1994 approximately.
- EMP weapons.
However, I agree this satellite has no nuclear reactor, simply because no project leader would see an advantage in having one.
Chances of hitting it: Absolutely excellent. A satellite is a sitting duck, with no manoeuvrability and a highly predictable trajectory as long as it's in space. 200 or 300km distance is nothing special to an appropriate missile. Only the satellite's speed is (much) higher than a plane's speed, but as long as the missile doesn't try to chase the target, it should be a mere question of software bounds and sensors angle-of-vision.
By the way, you don't need a warhead in the missile. At the satellite's speed, a Camembert is enough to destroy it. And the satellite wouldn't plunge in the ocean like a hit warplane: It would break into (many) pieces staying on slightly modified orbits, which would thus enter sooner the denser atmosphere.
Oh, I have no doubt that people can keep secrets when they believe it is in everyones interest to do so.
Launching a reactor into space is probably not in that catagory (a lot of people are anti ANYTHING nuclear) but a reactor coming to earth on an uncontrolled descent is definately NOT in that catagory.
Then you would find that one or more of those people who knew about it would be leaking word to the press.
As far as hitting the satellite, while it of course is doable, its also no piece of cake. You are essentially hitting a very high speed bullet with another bullet and thus with closing speeds on the order of 30,000 or more feet per second, the margin for error is incredibly small.
As far as "break into many pieces and staying on slightly modified orbits", I think that is somewhat of an understatement. Its a kinetic weapon and what it will do will remove kinetic energy from what it hits.
To put the change in perspective though, the Shuttle deorbits, from an even higher orbit, and does so within the same orbit, by simply changing its velocity by a bit less than 200 mph (or ~ 1% of its speed)
Arthur
Ps I didn't know there were machines that could read my mind. I guess that's a well kept secret.
- The NSA. How many building workers, bus drivers, cooks...? "No Such Agency".
- The hydrophones net at the Okhotsk sea. Not really cheap.
- Echelon.
- Mind-reading machines.
- Tempest. Existed in 1976 and probably before. Read it first in 1994 approximately.
- EMP weapons.
However, I agree this satellite has no nuclear reactor, simply because no project leader would see an advantage in having one.
Chances of hitting it: Absolutely excellent. A satellite is a sitting duck, with no manoeuvrability and a highly predictable trajectory as long as it's in space. 200 or 300km distance is nothing special to an appropriate missile. Only the satellite's speed is (much) higher than a plane's speed, but as long as the missile doesn't try to chase the target, it should be a mere question of software bounds and sensors angle-of-vision.
By the way, you don't need a warhead in the missile. At the satellite's speed, a Camembert is enough to destroy it. And the satellite wouldn't plunge in the ocean like a hit warplane: It would break into (many) pieces staying on slightly modified orbits, which would thus enter sooner the denser atmosphere.
Oh, I have no doubt that people can keep secrets when they believe it is in everyones interest to do so.
Launching a reactor into space is probably not in that catagory (a lot of people are anti ANYTHING nuclear) but a reactor coming to earth on an uncontrolled descent is definately NOT in that catagory.
Then you would find that one or more of those people who knew about it would be leaking word to the press.
As far as hitting the satellite, while it of course is doable, its also no piece of cake. You are essentially hitting a very high speed bullet with another bullet and thus with closing speeds on the order of 30,000 or more feet per second, the margin for error is incredibly small.
As far as "break into many pieces and staying on slightly modified orbits", I think that is somewhat of an understatement. Its a kinetic weapon and what it will do will remove kinetic energy from what it hits.
To put the change in perspective though, the Shuttle deorbits, from an even higher orbit, and does so within the same orbit, by simply changing its velocity by a bit less than 200 mph (or ~ 1% of its speed)
Arthur
Ps I didn't know there were machines that could read my mind. I guess that's a well kept secret.
Mind-reading: I know it for having observed it. And I believe it's done by machines, because I imagine more or less how machines could be built for it, but I can't imagine any physical natural process for humans to do it.
At the time I supposed such machines would analyze the minute electric or magnetic fields created by the brain's activity (like EEG and MEG do), I built jammers to protect myself. I did it as properly as possible - and I'm good for this - but they didn't help, so I'm convinced the mind-reading machines don't use these fields. Anyway, it would be extremely difficult at distances of 10m or even a bit more.
Then I thought to maps of brain's activity, like the ones researchers obtain today by MRI and other means. After learning which area of one particular brain is associated to each activity, physicians can read quite accurately what is going on - as precisely as distinguish each finger, for instance.
Do the same learning for the areas in charge of sight, hearing, or speaking, and mind-reading should be possible provided you make a map for each target person.
Then, of course, you need a machine that makes such pictures at some distance. Precisely at this point, we leave open science. I'd say: Pity, since these machines would have allowed medicine to make fast progress in brain diseases. The criminals at secret services have these machines already, so bringing them to honest people as well would be beneficial.
Possible ways to build such machines:
- Imaging radars. Blood must be more reflective than tissues, so they would see the activity on a picture (like in MRI). Use short wavelengths and image processing to improve the details. Nothing easy, but looks possible, and not worse than an MRI machine actually.
- Maybe with near infrared (using the Raman effect ?), as skin and hull are somewhat transparent there. Notice that Indian scientists have recently made a handheld and cheap IR device for emergency physicians to image brain strokes at the scene.
In both cases, contrast-enhancing molecules should be possible.
To protect myself, I now use a hat consisting of several plies of metalized plastic foil (a thin blanket made for wounded people). Much more comfortable and corrosion-resistant than an aluminium foil. Not for use outside however, if you care your reputation.
A full blanket of that same material also protects you and your desk, your computer etc against video cameras.
Whatever the wave and wavelength mind-reading machines use, they seem to be stopped by these hats - unless the users of such machines want to fool me; But as I was wrong with the jammers, they showed it to me. One nice thing with metalized foils is that they stop many waves and wavelengths.
The secret services' codename for mind-reading machines might be "science-fiction". They say "discret" when I use my hat. And they call me "Génère".
It's because of such machines that people knowing secrets have (= are given) worries: So they think to their worries instead of the secrets.
At the time I supposed such machines would analyze the minute electric or magnetic fields created by the brain's activity (like EEG and MEG do), I built jammers to protect myself. I did it as properly as possible - and I'm good for this - but they didn't help, so I'm convinced the mind-reading machines don't use these fields. Anyway, it would be extremely difficult at distances of 10m or even a bit more.
Then I thought to maps of brain's activity, like the ones researchers obtain today by MRI and other means. After learning which area of one particular brain is associated to each activity, physicians can read quite accurately what is going on - as precisely as distinguish each finger, for instance.
Do the same learning for the areas in charge of sight, hearing, or speaking, and mind-reading should be possible provided you make a map for each target person.
Then, of course, you need a machine that makes such pictures at some distance. Precisely at this point, we leave open science. I'd say: Pity, since these machines would have allowed medicine to make fast progress in brain diseases. The criminals at secret services have these machines already, so bringing them to honest people as well would be beneficial.
Possible ways to build such machines:
- Imaging radars. Blood must be more reflective than tissues, so they would see the activity on a picture (like in MRI). Use short wavelengths and image processing to improve the details. Nothing easy, but looks possible, and not worse than an MRI machine actually.
- Maybe with near infrared (using the Raman effect ?), as skin and hull are somewhat transparent there. Notice that Indian scientists have recently made a handheld and cheap IR device for emergency physicians to image brain strokes at the scene.
In both cases, contrast-enhancing molecules should be possible.
To protect myself, I now use a hat consisting of several plies of metalized plastic foil (a thin blanket made for wounded people). Much more comfortable and corrosion-resistant than an aluminium foil. Not for use outside however, if you care your reputation.
A full blanket of that same material also protects you and your desk, your computer etc against video cameras.
Whatever the wave and wavelength mind-reading machines use, they seem to be stopped by these hats - unless the users of such machines want to fool me; But as I was wrong with the jammers, they showed it to me. One nice thing with metalized foils is that they stop many waves and wavelengths.
The secret services' codename for mind-reading machines might be "science-fiction". They say "discret" when I use my hat. And they call me "Génère".
It's because of such machines that people knowing secrets have (= are given) worries: So they think to their worries instead of the secrets.
Shirley, you jest?
Arthur
Apparently the missile hit the target.
http://news.yahoo.com/s/ap/20080221/ap_on_.../dead_satellite
Arthur
http://news.yahoo.com/s/ap/20080221/ap_on_.../dead_satellite
Arthur
QUOTE (adoucette+Feb 20 2008, 11:47 PM)
Apparently the missile hit the target.
http://news.yahoo.com/s/ap/20080221/ap_on_.../dead_satellite
Arthur
Ata boy George,,,,,,,,,,,
http://news.yahoo.com/s/ap/20080221/ap_on_.../dead_satellite
Arthur
Ata boy George,,,,,,,,,,,
QUOTE (paul h+Feb 21 2008, 11:13 AM)
Ata boy George,,,,,,,,,,,
Yep, way to go....
The Russians and Chinese (cry babies) are now going to find it dang nearly impossible to get any spy satellite secrets now that it exists as 10,000 pieces of junk, each with its own orbital trajectory for re-entry. Mission accomplished boys.
Bloody good show.
JW
Yep, way to go....
The Russians and Chinese (cry babies) are now going to find it dang nearly impossible to get any spy satellite secrets now that it exists as 10,000 pieces of junk, each with its own orbital trajectory for re-entry.
Mission accomplished boys.Bloody good show.
JW
And since it worked, will the armed forces call it a hitile instead of a missile?
What, you're sniggering? Maybe you ignore Nato had begun to do this some decades ago.
What, you're sniggering? Maybe you ignore Nato had begun to do this some decades ago.
So,, now I have to wonder how long the posted tracking link will continue to track it. (If it is now in a few thousand pieces that is) 
http://www.heavens-above.com/orbitdisplay.asp?satid=29651
http://www.heavens-above.com/orbitdisplay.asp?satid=29651
The site is not actually tracking the satellite (or its pieces) its just projecting the orbital elements ahead in time on a map of the globe.
See http://www.heavens-above.com/usa193.aspx?l...ed&alt=0&tz=CET
For more info on the debris
Arthur
See http://www.heavens-above.com/usa193.aspx?l...ed&alt=0&tz=CET
For more info on the debris
Arthur
QUOTE (Enthalpy+Feb 21 2008, 05:07 PM)
And since it worked, will the armed forces call it a hitile instead of a missile?
What, you're sniggering? Maybe you ignore Nato had begun to do this some decades ago.
Ha. Ha...I have to laugh at the Chinese trying to make it look like we are testing how to knock satellites out of orbit..
Don't these morons know America has ALREADY had that capability for years?
Do the Chinese really think we are going to allow THEM to develop anti-satellite technology without us having the ability to take them out..... ? DUH?
Welcome to the 21st century China.....
HERE"S THE REAL reason we took out USA 193......
From Cartwright at the Pentagon (as reported on Yahoo):
"The size of the debris is smaller than the Pentagon had forecast and MOST OF THE SATELLITES INTELLIGENCE CAPABILITY was likely destroyed, Cartwright said. Analysts had said one of the reasons for the shootdown was that officials worried that without it, larger chunks of the satellite could fall and BE RECOVERED, opening the possibility of secret technology FALLING INTO THE HANDS OF THE CHINESE or others". (bold added by me).
Make no mistake....That was THE reason for the shot down..
No wonder the Chinese are being such cry babies....they lost all chance to steal more of our advanced technology.
Let the space wars begin....er, ...continue.
JW
What, you're sniggering? Maybe you ignore Nato had begun to do this some decades ago.
Ha. Ha...I have to laugh at the Chinese trying to make it look like we are testing how to knock satellites out of orbit..
Don't these morons know America has ALREADY had that capability for years?
Do the Chinese really think we are going to allow THEM to develop anti-satellite technology without us having the ability to take them out..... ? DUH?
Welcome to the 21st century China.....
HERE"S THE REAL reason we took out USA 193......
From Cartwright at the Pentagon (as reported on Yahoo):
"The size of the debris is smaller than the Pentagon had forecast and MOST OF THE SATELLITES INTELLIGENCE CAPABILITY was likely destroyed, Cartwright said. Analysts had said one of the reasons for the shootdown was that officials worried that without it, larger chunks of the satellite could fall and BE RECOVERED, opening the possibility of secret technology FALLING INTO THE HANDS OF THE CHINESE or others". (bold added by me).
Make no mistake....That was THE reason for the shot down..
No wonder the Chinese are being such cry babies....they lost all chance to steal more of our advanced technology.
Let the space wars begin....er, ...continue.
JW
>....they lost all chance to steal more of our advanced technology.
Until Lockheed Martin discovers that it is cheaper to have the Chinese do the manufacturing over there and farms it out to them.
Until Lockheed Martin discovers that it is cheaper to have the Chinese do the manufacturing over there and farms it out to them.
I'm sure there are already Chinese spies working for Lockheed Martin. 
The S3
http://www.designation-systems.net/dusrm/m-161.html
The planned upgrades look impressive as well.
Arthur
http://www.designation-systems.net/dusrm/m-161.html
The planned upgrades look impressive as well.
Arthur
I bet the Iranians wish they had a few of those puppies.
(could you say bye, bye Israel)
(could you say bye, bye Israel)
QUOTE (barakn+Feb 21 2008, 02:59 PM)
I'm sure there are already Chinese spies working for Lockheed Martin.
I live very near Lockheed Martin (in the Antelope Valley) most of the Chinese here seem to have resturants and there aren't nearly enough of them. I like to find the best (cheap) resturants in whatever town I am in. We are not exactly crawling with Chinese folks here.
I am sure there are ways of keeping potential spys out of such important business, no?
I live very near Lockheed Martin (in the Antelope Valley) most of the Chinese here seem to have resturants and there aren't nearly enough of them. I like to find the best (cheap) resturants in whatever town I am in. We are not exactly crawling with Chinese folks here.
I am sure there are ways of keeping potential spys out of such important business, no?
QUOTE (paul h+Feb 21 2008, 08:36 PM)
>....they lost all chance to steal more of our advanced technology.
Until Lockheed Martin discovers that it is cheaper to have the Chinese do the manufacturing over there and farms it out to them.
Or some Bozo military 'anlayst' for the Pentagon decides to sell out for a weekend in Vegas, a couple hundred $ in poker chips, and a night with the resident Chinese 'hoe' (that's what they call em in Texas)......like the one caught last week in New Orleans.....
http://www.breitbart.com/article.php?id=D8...&show_article=1
Makes me wish I had never voted to remove the death penalty.
JW
Until Lockheed Martin discovers that it is cheaper to have the Chinese do the manufacturing over there and farms it out to them.
Or some Bozo military 'anlayst' for the Pentagon decides to sell out for a weekend in Vegas, a couple hundred $ in poker chips, and a night with the resident Chinese 'hoe' (that's what they call em in Texas)......like the one caught last week in New Orleans.....
http://www.breitbart.com/article.php?id=D8...&show_article=1
Makes me wish I had never voted to remove the death penalty.
JW
Do you realize that rockets and satellites are yesterday's technology ?
They are now half a century old. They have made little progress since 1969, only incorporating advances in external technology like semiconductors or materials.
Less-than-top technology countries are able of developing rockets and satellites by themselves. Dozens have done it. No need for spying there.
You know, what was barely achievable for a big country half a century ago can now be made by ten people in a club, just because the rest of knowledge and technology has evolved so much.
They are now half a century old. They have made little progress since 1969, only incorporating advances in external technology like semiconductors or materials.
Less-than-top technology countries are able of developing rockets and satellites by themselves. Dozens have done it. No need for spying there.
You know, what was barely achievable for a big country half a century ago can now be made by ten people in a club, just because the rest of knowledge and technology has evolved so much.
QUOTE (Enthalpy+Feb 22 2008, 11:57 PM)
Do you realize that rockets and satellites are yesterday's technology ?
They are now half a century old. They have made little progress since 1969, only incorporating advances in external technology like semiconductors or materials.
Less-than-top technology countries are able of developing rockets and satellites by themselves. Dozens have done it. No need for spying there.
Ha, ha....
That's like saying cars have been built since 1908 and nothing new has happened since then...gee... they all have 4 tires and a steering wheel.....nothing has changed.
Why don't you try to convince the Chinese they REALLY don't need to spend hundreds of millions of $ and employ thousands of foreign 'agents' for something that you consider totally unnecessary.....Maybe you can convince them.
Think enthalpy..... about what you just said , and I think you will realize the total naivety those comments.
I can't believe I even have to respond to this.
JW
They are now half a century old. They have made little progress since 1969, only incorporating advances in external technology like semiconductors or materials.
Less-than-top technology countries are able of developing rockets and satellites by themselves. Dozens have done it. No need for spying there.
Ha, ha....
That's like saying cars have been built since 1908 and nothing new has happened since then...gee... they all have 4 tires and a steering wheel.....nothing has changed.
Why don't you try to convince the Chinese they REALLY don't need to spend hundreds of millions of $ and employ thousands of foreign 'agents' for something that you consider totally unnecessary.....Maybe you can convince them.
Think enthalpy..... about what you just said , and I think you will realize the total naivety those comments.
I can't believe I even have to respond to this.
JW
I'm absolutely serious. I built a satellite in a club (search Sara and Esieespace on the Web), so I know how difficult or easy it is.
Employing agents:
- These don't need to be useful to get paid.
- But US agents need to convince US citizens that Chinese agents spy, in order to get paid by naive taxpayers.
And by the way, agents tried several times to bring me stolen technology. What they brought was complete crap.
Basically, if someone is able to recognize an interesting idea, he's able of having the idea by himself. Spying is just a perverse pastime, nothing useful.
Employing agents:
- These don't need to be useful to get paid.
- But US agents need to convince US citizens that Chinese agents spy, in order to get paid by naive taxpayers.
And by the way, agents tried several times to bring me stolen technology. What they brought was complete crap.
Basically, if someone is able to recognize an interesting idea, he's able of having the idea by himself. Spying is just a perverse pastime, nothing useful.
QUOTE (Enthalpy+Feb 23 2008, 01:48 AM)
Spying is just a perverse pastime, nothing useful.
I still can't believe you level of naivety.....It is well known that Chinese espioage at all levels,( military, technological, and economic), is way out of hand and at or beyond the cold war levels.
Maybe you should try to convince the Communist Chinese that their spying is producing "nothing useful" as you say....I'm sure they are getting a good laugh out of that ...and would probably offer to pay handily if you could convince the US counter-intelligence people to believe the same foolishness..
Meantime I suggest you educate yourself.......You can start here....
http://www.usatoday.com/money/world/2007-0...ina-spy-1_N.htm
Here's some quotes ......
"China's technology-targeting differs from classic Cold War-era spying, which pitted American intelligence agents against their KGB counterparts. Along with using intelligence professionals, China seeks to capitalize on some of the thousands of Chinese and Chinese-American engineers, researchers, scientists and students who fill key positions in U.S. industry and academia, say current and former U.S. counterintelligence officials."
"This is not some 'yellow peril' witch hunt. … The counterintelligence environment in terms of China right now is just white-hot," says James Mulvenon, director of the Center for Intelligence Research and Analysis, a Washington, D.C., think tank that advises U.S. intelligence agencies".
"In some cases, individuals stealing trade secrets execute Beijing's orders. That's what the Justice Department says occurred with Chi Mak, 66, who was born in Guangzhou, was educated in Shanghai and became a naturalized U.S. citizen in 1985. He obtained a "secret"-level security clearance in 1996."
FBI agents found four Chinese-language "tasking lists" in Mak's trash, which they say itemized specific technologies that China covets, such as "aircraft carrier electronic systems" and "submarine propulsion technology." One of the lists also directed Mak, a senior engineer working on power systems for Navy submarines, to join professional associations and attend advanced research seminars"
Don't worry ...all they want is all that NON USEFUL stuff like "submarine propulsion technology" and "aircraft carrier electronics"...
Please ........if you don' get it by now...
I'm sorry....I really don't think I will continue to respond to such naivety, Enthalpy.
JW
Here is some follow up on questions that still linger.
More questions
More questions
Spies exist because they get paid for their criminal activity. Not because they are useful, but because they can convince politicians and the public to pay them.
Counterspying exist for the same reasons.
Information brought by spies is always valueless. Hence counterspying is useless as well.
And the criminal activities of counterspies is extremely counterproductive for the companies they pretend to protect.
Anyway, spying or fighting against terrorism is just a minute activity of secret services.
As the Soviet Union went down, secret services discovered a new allegedly global threat they called Al Qaida and put this name on any bombing in the World - even on the low-intensity war between Indonesia and Australia for the control of East Timor. Now that people realize Al Qaida had no ties with Saddam (and the report on WMD was a fake) and are less willing to believe the threat by Al Qaida, secret services invent Chinese spying.
I won't cite any newspaper article inspired by a newsconference at some agency. I have my own experience, since my father worked at the Nato, at an embassy and several consulates, I worked several times for the weapons industry, at Ariane and at research centers, and filed several patents.
You know what? As a scientist, I'm not influenced just by a single word like "naive". I even like to believe I think using full sentences.
Secret services are a plague. We can suppress them unilaterally, this would be a big benefit for ourselves.
Counterspying exist for the same reasons.
Information brought by spies is always valueless. Hence counterspying is useless as well.
And the criminal activities of counterspies is extremely counterproductive for the companies they pretend to protect.
Anyway, spying or fighting against terrorism is just a minute activity of secret services.
As the Soviet Union went down, secret services discovered a new allegedly global threat they called Al Qaida and put this name on any bombing in the World - even on the low-intensity war between Indonesia and Australia for the control of East Timor. Now that people realize Al Qaida had no ties with Saddam (and the report on WMD was a fake) and are less willing to believe the threat by Al Qaida, secret services invent Chinese spying.
I won't cite any newspaper article inspired by a newsconference at some agency. I have my own experience, since my father worked at the Nato, at an embassy and several consulates, I worked several times for the weapons industry, at Ariane and at research centers, and filed several patents.
You know what? As a scientist, I'm not influenced just by a single word like "naive". I even like to believe I think using full sentences.
Secret services are a plague. We can suppress them unilaterally, this would be a big benefit for ourselves.
Watching the explosion of the spy satellite I noticed that it was very spherical. Would not the missile velocity have caused a different pattern for the explosion?
Because I am a new member on this board I'm unable to include a link to the news clip as I post replies. Perhaps someone that is able could post the link for me. I saw it on msnbc entitled "Military says it hit satellite".
I was wondering if something could have been so sensitive/dangerous on this satellite that it had an explosive device on board ever since it was launched and the navy rocket was a ruse.
I am also skeptical because to this point the technology for targeting objects in space has been heat seeking and this would have required some alternative and all the headaches that would involve being solved in a very short time frame.
Because I am a new member on this board I'm unable to include a link to the news clip as I post replies. Perhaps someone that is able could post the link for me. I saw it on msnbc entitled "Military says it hit satellite".
I was wondering if something could have been so sensitive/dangerous on this satellite that it had an explosive device on board ever since it was launched and the navy rocket was a ruse.
I am also skeptical because to this point the technology for targeting objects in space has been heat seeking and this would have required some alternative and all the headaches that would involve being solved in a very short time frame.
>I was wondering if something could have been so sensitive/dangerous on this satellite that it had an explosive device on board ever since it was launched and the navy rocket was a ruse.
What? You don't buy the hydrazine thingy?
What? You don't buy the hydrazine thingy?
Hydrazine could have been there as well, although I question why it would not have been used to sustain orbit.
QUOTE (student4ever+Feb 28 2008, 05:40 PM)
Hydrazine could have been there as well, although I question why it would not have been used to sustain orbit.
The computer failed to boot from day one.
The computer failed to boot from day one.
Was it possible to explode the hydrazine? Was there enough water and methane present for the hydrazine to "burn"?
>Was it possible to explode the hydrazine?
They did,, They just used a rocket to do with. No way to explode the tank with out a working computer on board. And if the computer was working then there would be no need to.
They did,, They just used a rocket to do with. No way to explode the tank with out a working computer on board. And if the computer was working then there would be no need to.
QUOTE (tikay+Feb 22 2008, 02:53 AM)
I live very near Lockheed Martin (in the Antelope Valley) most of the Chinese here seem to have resturants and there aren't nearly enough of them. I like to find the best (cheap) resturants in whatever town I am in. We are not exactly crawling with Chinese folks here.
I am sure there are ways of keeping potential spys out of such important business, no?
A Chinese spy doesn't need to be Chinese, a Chinese spy can be anyone willing to trade sensitive information for Chinese money, or to support Communist ideals, or to get revenge on their own government, or....
I here you about the food. I like Szechuan.
I am sure there are ways of keeping potential spys out of such important business, no?
A Chinese spy doesn't need to be Chinese, a Chinese spy can be anyone willing to trade sensitive information for Chinese money, or to support Communist ideals, or to get revenge on their own government, or....
I here you about the food. I like Szechuan.
Pattern of the explosion:
The missile had no warhead. Right choice, as the shear velocity of the satellite (the missile contributes also) brings more energy per kilogram than an explosive.
So yes, I also expected a long pattern instead of a spherical one. However, we may be fooled by the angle of sight.
Next possibility: The missile took only little material from the satellite along a straight pattern. Most of the satellite may have dispersed with a smaller velocity as a sphere around the initial trajectory of the satellite.
Also: Some years ago, antisatellite missiles were depicted as unfolding umbrellas, in order to hit directly more parts of the satellite. This might give a spherical pattern.
I consider likely that hydrazine (or MMH or UDMH, generally preferred to real hydrazine) detonated by such a brutal shock. These chemicals are endothermic and should detonate if properly ignited, without needing an oxidizer. I don't know a relation to methane nor water.
Real hydrazine isn't very common now on satellites; It's used without an oxidizer, by catalytic decomposition in the engine. Engineers now prefer more efficient bi-liquids: N2O4, then in combination with MMH or UDMH. The mix catches fire by contact. A missile impact would provoke a "contact".
So although I expected a straight debris pattern, the spherical pattern has several possible causes - even if US193 wasn't a weapon.
The missile had no warhead. Right choice, as the shear velocity of the satellite (the missile contributes also) brings more energy per kilogram than an explosive.
So yes, I also expected a long pattern instead of a spherical one. However, we may be fooled by the angle of sight.
Next possibility: The missile took only little material from the satellite along a straight pattern. Most of the satellite may have dispersed with a smaller velocity as a sphere around the initial trajectory of the satellite.
Also: Some years ago, antisatellite missiles were depicted as unfolding umbrellas, in order to hit directly more parts of the satellite. This might give a spherical pattern.
I consider likely that hydrazine (or MMH or UDMH, generally preferred to real hydrazine) detonated by such a brutal shock. These chemicals are endothermic and should detonate if properly ignited, without needing an oxidizer. I don't know a relation to methane nor water.
Real hydrazine isn't very common now on satellites; It's used without an oxidizer, by catalytic decomposition in the engine. Engineers now prefer more efficient bi-liquids: N2O4, then in combination with MMH or UDMH. The mix catches fire by contact. A missile impact would provoke a "contact".
So although I expected a straight debris pattern, the spherical pattern has several possible causes - even if US193 wasn't a weapon.
Pretty funny.
Post a link to a 20 year old article about a reactor system that was never flown and whose project funding ended in 1995.
Paranoid much?
Arthur
Post a link to a 20 year old article about a reactor system that was never flown and whose project funding ended in 1995.
Paranoid much?
Arthur
Dear Arthur;
Our math is as different as our approach to intellectual discourse.
The article was published in March of 2008. Thats this month, not twenty years ago. But then again I understand the your need for the comfort of denial. Its the intellecual equvalent of a passifier.
Again, a little more study and a little less apologetic propaganda would do wonders for your credibility.
Gavilan
Our math is as different as our approach to intellectual discourse.
The article was published in March of 2008. Thats this month, not twenty years ago. But then again I understand the your need for the comfort of denial. Its the intellecual equvalent of a passifier.
Again, a little more study and a little less apologetic propaganda would do wonders for your credibility.
Gavilan
QUOTE (Gavilan+Mar 7 2008, 10:07 AM)
Dear Arthur;
Our math is as different as our approach to intellectual discourse.
The article was published in March of 2008. Thats this month, not twenty years ago. But then again I understand the your need for the comfort of denial. Its the intellecual equvalent of a passifier.
Again, a little more study and a little less apologetic propaganda would do wonders for your credibility.
Gavilan
Really?
Let's see, what does it say right at the START of the friggin article:
By WILLIAM J. BROAD
Published: October 18, 1988
Hmmmm?
2008 - 1988 = 20 years.
Does YOUR math not work this way?
Hint: If you do news searches you will also get archived data.
A little more STUDY, a little less JUMPING to self serving CONCLUSIONS and a LOT LESS PARANOIA would do you wonders and maybe start to repair your tarnished credibility.
Arthur
Our math is as different as our approach to intellectual discourse.
The article was published in March of 2008. Thats this month, not twenty years ago. But then again I understand the your need for the comfort of denial. Its the intellecual equvalent of a passifier.
Again, a little more study and a little less apologetic propaganda would do wonders for your credibility.
Gavilan
Really?
Let's see, what does it say right at the START of the friggin article:
By WILLIAM J. BROAD
Published: October 18, 1988
Hmmmm?
2008 - 1988 = 20 years.
Does YOUR math not work this way?
Hint: If you do news searches you will also get archived data.
A little more STUDY, a little less JUMPING to self serving CONCLUSIONS and a LOT LESS PARANOIA would do you wonders and maybe start to repair your tarnished credibility.
Arthur
I stand corrected. The New York Times article was indeed written in 1988.
http://www.google.com/search?q=Space+React...n&start=10&sa=N
www.space.com/news/nasa_nuclear_020205.html
www.princeton.edu/~globsec/publications/pdf/1_1-2Primack.pdf
www.ornl.gov/~webworks/cppr/y2001/pres/122984.pdf
www.sciencemag.org/cgi/reprint/243/4890/476.pdf
More old news from http://query.nytimes.com/gst/fullpage.html...753C1A961948260
"The Federal Government is moving ahead with plans to put nuclear reactors and nuclear rocket engines in space for both civilian and military uses. Orbiting reactors, officials believe, will be essential for powering antimissile weapons and future scientific missions."
http://stinet.dtic.mil/oai/oai?verb=getRec...ifier=ADA338871
http://www.google.com/search?q=Space+React...n&start=10&sa=N
www.space.com/news/nasa_nuclear_020205.html
www.princeton.edu/~globsec/publications/pdf/1_1-2Primack.pdf
www.ornl.gov/~webworks/cppr/y2001/pres/122984.pdf
www.sciencemag.org/cgi/reprint/243/4890/476.pdf
More old news from http://query.nytimes.com/gst/fullpage.html...753C1A961948260
"The Federal Government is moving ahead with plans to put nuclear reactors and nuclear rocket engines in space for both civilian and military uses. Orbiting reactors, officials believe, will be essential for powering antimissile weapons and future scientific missions."
http://stinet.dtic.mil/oai/oai?verb=getRec...ifier=ADA338871
We pulled the plug on those projects back in the mid 90s.
Arthur
Arthur
QUOTE (adoucette+Mar 7 2008, 09:52 PM)
We pulled the plug on those projects back in the mid 90s.
Arthur
The most likely candidate was probably an earlier model of this.
http://gltrs.grc.nasa.gov/Citations.aspx?id=1400
AND SUBTITLE:
Advanced Stirling Technology Development at NASA Glenn Research Center
AUTHOR(S):
Shaltens, Richard, K.; Wong, Wayne, A.
REPORT DATE:
2007-09-01
FUNDING NUMBERS:
WBS 138494.04.01.01
PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES):
National Aeronautics and Space Administration John H. Glenn Research Center at Lewis Field Cleveland, Ohio 44135-3191
PERFORMING ORGANIZATION REPORT NUMBER:
E-16126
SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES):
National Aeronautics and Space Administration Washington, DC 20546-0001
REPORT TYPE AND DATES COVERED:
Technical Memorandum
SPONSORING/MONITORING AGENCY REPORT NUMBER:
NASA/TM-2007-214930
SUPPLEMENTARY NOTES:
ABSTRACT:
The NASA Glenn Research Center has been developing advanced energy-conversion technologies for use with both radioisotope power systems and fission surface power systems for many decades. Under NASA’s Science Mission Directorate, Planetary Science Theme, Technology Program, Glenn is developing the next generation of advanced Stirling convertors (ASCs) for use in the Department of Energy/Lockheed Martin Advanced Stirling Radioisotope Generator (ASRG). The next-generation power-conversion technologies require high efficiency and high specific power (watts electric per kilogram) to meet future mission requirements to use less of the Department of Energy’s plutonium-fueled general-purpose heat source modules and reduce system mass. Important goals include long-life (>14-yr) reliability and scalability so that these systems can be considered for a variety of future applications and missions including outer-planet missions and continual operation on the surface of Mars. This paper provides an update of the history and status of the ASC being developed for Glenn by Sunpower Inc. of Athens, Ohio.
SUBJECT TERMS:
Radioisotope power systems; Fission power systems; Stirling conversion systems; Stirling convertors
2006 - http://gltrs.grc.nasa.gov/Citations.aspx?id=258
More recent
PDF] A Practical Approach to Starting Fission Surface Power Development 100% ||||||||||||||||||||
... Fission Surface Power Development ... Recent trade studies by the JIMO/NR team and LANL
have produced two distinct paths for space fission power systems. ... 2006-08-29
+ Highlighted
http://gltrs.grc.nasa.gov/reports/2006/TM-2006-214366.pdf
[PDF] A Comparison of Fission Power System Options for Lunar and Mars ... 100% ||||||||||||||||||||
... A Comparison of Fission Power System Options for Lunar and Mars Surface Applications
NASA/TM���2006-214120 February 2006 ... A Comparison of Fission Power System ... 2006-03-07 + Highlighted
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[ More results from gltrs.grc.nasa.gov/reports/2006 ]
NASA SBIR & STTR 2006 Solicitations : TOPIC X8 Energy Generation ... 90% ||||||||||||||||||||
... X8.01 Non-Toxic Launch Vehicle Power for Thrust Vector and Engine Actuation X8.02
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Research Page 12. ... timeframe Nuclear Fission Power Research Page 13. ... 2004-03-15
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supercriticality condition, thereby, releasing an intense pulse fission power. ... 2005-10-02
+ Highlighted
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NASA SBIR & STTR 2005 Solicitations : TOPIC X10 Prometheus ... 60% ||||||||||||||||||||
... Critical Technologies for In-Space Application of Nuclear Thermal Propulsion
X10.03 Critical Technologies for Space-Based Nuclear Fission Power Systems X10.04 ... 2005-07-06
+ Highlighted
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this activity is focused on space fission power systems. The ... 2006-04-01
+ Highlighted
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NASA SBIR and STTR 2006 Taxonomy Subtopics 40% ||||||||||||||||||||
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Fission Power Technologies. Photovoltaic Conversion, S2 ... 2007-06-28 + Highlighted
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Arthur
The most likely candidate was probably an earlier model of this.
http://gltrs.grc.nasa.gov/Citations.aspx?id=1400
AND SUBTITLE:
Advanced Stirling Technology Development at NASA Glenn Research Center
AUTHOR(S):
Shaltens, Richard, K.; Wong, Wayne, A.
REPORT DATE:
2007-09-01
FUNDING NUMBERS:
WBS 138494.04.01.01
PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES):
National Aeronautics and Space Administration John H. Glenn Research Center at Lewis Field Cleveland, Ohio 44135-3191
PERFORMING ORGANIZATION REPORT NUMBER:
E-16126
SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES):
National Aeronautics and Space Administration Washington, DC 20546-0001
REPORT TYPE AND DATES COVERED:
Technical Memorandum
SPONSORING/MONITORING AGENCY REPORT NUMBER:
NASA/TM-2007-214930
SUPPLEMENTARY NOTES:
ABSTRACT:
The NASA Glenn Research Center has been developing advanced energy-conversion technologies for use with both radioisotope power systems and fission surface power systems for many decades. Under NASA’s Science Mission Directorate, Planetary Science Theme, Technology Program, Glenn is developing the next generation of advanced Stirling convertors (ASCs) for use in the Department of Energy/Lockheed Martin Advanced Stirling Radioisotope Generator (ASRG). The next-generation power-conversion technologies require high efficiency and high specific power (watts electric per kilogram) to meet future mission requirements to use less of the Department of Energy’s plutonium-fueled general-purpose heat source modules and reduce system mass. Important goals include long-life (>14-yr) reliability and scalability so that these systems can be considered for a variety of future applications and missions including outer-planet missions and continual operation on the surface of Mars. This paper provides an update of the history and status of the ASC being developed for Glenn by Sunpower Inc. of Athens, Ohio.
SUBJECT TERMS:
Radioisotope power systems; Fission power systems; Stirling conversion systems; Stirling convertors
2006 - http://gltrs.grc.nasa.gov/Citations.aspx?id=258
More recent
PDF] A Practical Approach to Starting Fission Surface Power Development 100% ||||||||||||||||||||
... Fission Surface Power Development ... Recent trade studies by the JIMO/NR team and LANL
have produced two distinct paths for space fission power systems. ... 2006-08-29
+ Highlighted
http://gltrs.grc.nasa.gov/reports/2006/TM-2006-214366.pdf
[PDF] A Comparison of Fission Power System Options for Lunar and Mars ... 100% ||||||||||||||||||||
... A Comparison of Fission Power System Options for Lunar and Mars Surface Applications
NASA/TM���2006-214120 February 2006 ... A Comparison of Fission Power System ... 2006-03-07 + Highlighted
http://gltrs.grc.nasa.gov/reports/2006/TM-2006-214120.pdf
[ More results from gltrs.grc.nasa.gov/reports/2006 ]
NASA SBIR & STTR 2006 Solicitations : TOPIC X8 Energy Generation ... 90% ||||||||||||||||||||
... X8.01 Non-Toxic Launch Vehicle Power for Thrust Vector and Engine Actuation X8.02
Space Based Nuclear Fission Power Technologies X8.03 Space Rated Batteries ... 2006-07-06 + Highlighted
http://sbir.gsfc.nasa.gov/SBIR/sbirsttr200...R/TOPIC_X8.html - 14k
[PDF] NASA���s Nuclear Systems Initiative Overview 70% ||||||||||||||||||||
... atmosphere probes ��� Allows higher bandwidth communications Nuclear Fission Power
Research Page 12. ... timeframe Nuclear Fission Power Research Page 13. ... 2004-03-15
+ Highlighted
http://eos.gsfc.nasa.gov/eos-ll/docs/nuclear_syst_init.pdf
NASA SBIR 01-1 Solicitation 70% ||||||||||||||||||||
... small volume (~ 1 m3) of a fissile (235U, 233U, or 239Pu) compound gas to prompt
supercriticality condition, thereby, releasing an intense pulse fission power. ... 2005-10-02
+ Highlighted
http://sbir.gsfc.nasa.gov/SBIR/abstracts/0...A6.01-8948.html - 4k
(S-8) Nuclear Energy 60% ||||||||||||||||||||
... Nuclear Waste. The trouble with fission power is that the "fission fragments" from
the break-up of uranium or plutonium are very "hot, " extremely radioactive. ... 1999-09-01
+ Highlighted
http://www-spof.gsfc.nasa.gov/stargaze/Snuclear.htm - 30k
NASA SBIR & STTR 2005 Solicitations : TOPIC X10 Prometheus ... 60% ||||||||||||||||||||
... Critical Technologies for In-Space Application of Nuclear Thermal Propulsion
X10.03 Critical Technologies for Space-Based Nuclear Fission Power Systems X10.04 ... 2005-07-06
+ Highlighted
http://sbir.gsfc.nasa.gov/SBIR/sbirsttr200.../TOPIC_X10.html - 25k
Closed Brayton Power System Prototype Developed for Future Space ... 50% ||||||||||||||||||||
... bearings. The heat source can be solar, fission, or radioisotope; however,
this activity is focused on space fission power systems. The ... 2006-04-01
+ Highlighted
http://www.grc.nasa.gov/WWW/RT/2006/RP/RPT-mason.html - 8k
NASA SBIR and STTR 2006 Taxonomy Subtopics 40% ||||||||||||||||||||
... Space Missions; T3.01 - Space Power and Propulsion; X8.02 - Space Based Nuclear
Fission Power Technologies. Photovoltaic Conversion, S2 ... 2007-06-28 + Highlighted
http://sbir.nasa.gov/SBIR/sbirsttr2006/sol...n/tax_sub2.html - 101k
QUOTE (Gavilan+Mar 8 2008, 03:35 AM)
The most likely candidate was probably an earlier model of this.
Most likely candidate for WHAT?
These new Sterling converters are under still under development.
http://gltrs.grc.nasa.gov/reports/2007/TM-2007-214930.pdf
Arthur
I worked on the SM-3/KW program for about a year. They don't need a warhead, the kinetic energy of the closing velocities make the energy density greater than you get from high-explosives. Cheese would indeed be as effective at destroying a target with the closing speeds we're talking about.
I've seen the test results (videos) of the targets getting hit by the SM-3/KW, and the term "debris" truly misses the point, the targets turn into clouds of incandescent smoke.
BTW, a school-bus-sized satellite *would* be one of the smaller satellites launched these days.
And the satellites (especially the radar satellites) launched by the US wouldn't have the same need for high power as Russian/Soviet radar satellites. US radar technology is far more sophisticated than Russian radar technology, as is US solar cell technology. Those two facts, combined with the different political systems and cultural differences account for the fact that the vast majority of reactors in-orbit these days are Soviet-built. The Soviets required their high school students to study a lot more physics than American high school students do, and a lot less time on "Gaia"-type BS. Soviet radars *needed* more energy, and Soviet engineers were a lot less frightened by nuclear energy (over-hyped by Western Greenpeace-types), because advanced radars require advanced computers, and their chip technology isn't as advanced as ours. Neither is their solar cell technology, so getting the same power would require lots bigger solar panels, and they'd need lots more power to run their radars than we need.
If you're worried about radiation, you really should be more concerned about coal-powered electrical power plants. They emit a lot more radioactive isotopes into the air than nuclear power plants or nuclear-powered satellites.
I, personally, would be more worried about the hydrazine, which is pretty much what they said at the time.
And target missiles are a lot cheaper and easier to control for testing SM-3/KW than spy satellites.
And, BTW, *nobody* has ever even gotten close to being able to read anybody's minds by any means, regardless of whatever imagery you've seen or BS you've read. The brain is FAR too complex for some MRI-type device to even be useful as a lie-detector (something that should be far simpler than "reading minds") which are used routinely in the intelligence industry to catch people who've started selling secrets or have changed sides. And they haven't been very successful at that, and that's with the person strapped-in and hooked-up to various sensors. And, if you could actually *read* someone's mind, why would you bother waterboarding captured terrorists?
And if you could *read* someone's mind from a distance, you wouldn't need to have air passengers take their shoes off and get frisked.
And if *satellites* could "read" minds, we would be having a lot more luck finding Al Qaida terrorists and Iraqi insurgents, wouldn't you think?
So you can put away your tin-foil hats, folks. Satellites can't read minds. (I wish they could.)
I've seen the test results (videos) of the targets getting hit by the SM-3/KW, and the term "debris" truly misses the point, the targets turn into clouds of incandescent smoke.
BTW, a school-bus-sized satellite *would* be one of the smaller satellites launched these days.
And the satellites (especially the radar satellites) launched by the US wouldn't have the same need for high power as Russian/Soviet radar satellites. US radar technology is far more sophisticated than Russian radar technology, as is US solar cell technology. Those two facts, combined with the different political systems and cultural differences account for the fact that the vast majority of reactors in-orbit these days are Soviet-built. The Soviets required their high school students to study a lot more physics than American high school students do, and a lot less time on "Gaia"-type BS. Soviet radars *needed* more energy, and Soviet engineers were a lot less frightened by nuclear energy (over-hyped by Western Greenpeace-types), because advanced radars require advanced computers, and their chip technology isn't as advanced as ours. Neither is their solar cell technology, so getting the same power would require lots bigger solar panels, and they'd need lots more power to run their radars than we need.
If you're worried about radiation, you really should be more concerned about coal-powered electrical power plants. They emit a lot more radioactive isotopes into the air than nuclear power plants or nuclear-powered satellites.
I, personally, would be more worried about the hydrazine, which is pretty much what they said at the time.
And target missiles are a lot cheaper and easier to control for testing SM-3/KW than spy satellites.
And, BTW, *nobody* has ever even gotten close to being able to read anybody's minds by any means, regardless of whatever imagery you've seen or BS you've read. The brain is FAR too complex for some MRI-type device to even be useful as a lie-detector (something that should be far simpler than "reading minds") which are used routinely in the intelligence industry to catch people who've started selling secrets or have changed sides. And they haven't been very successful at that, and that's with the person strapped-in and hooked-up to various sensors. And, if you could actually *read* someone's mind, why would you bother waterboarding captured terrorists?
And if you could *read* someone's mind from a distance, you wouldn't need to have air passengers take their shoes off and get frisked.
And if *satellites* could "read" minds, we would be having a lot more luck finding Al Qaida terrorists and Iraqi insurgents, wouldn't you think?
So you can put away your tin-foil hats, folks. Satellites can't read minds. (I wish they could.)
Yes, mind-reading works, as I've seen it. But I don't ask you, and I don't need you, to believe it. Simply, don't tell "it's impossible" without really solid evidence. I also said "Star wars programme is impossible" when it started, and now it works - even the laser weapons against which I saw fundamental physical reasons.
I've never written anything about brain-reading satellites. Distance is too big to make a picture. About MRI, read a bit before speaking.
A space blanket is far better than a tin foil as a hat against mind-reading. Much more durable and comfortable.
Yes, Soviet engineers were less cautious with nuclear reactors, and they got serious accidents, in submarines among others. And for radioactivity coming from coal: In Europe, fumes are filtered away at power plants exhausts for 30 years. You should obtain it from your government if you believe they're radioactive.
Waterboarding is a means of terrorizing people. Torture doesn't serve to get information.
Any reasoning like "if they head this, they wouldn't do that" is useless because you don't know why other people decide something.
I've never written anything about brain-reading satellites. Distance is too big to make a picture. About MRI, read a bit before speaking.
A space blanket is far better than a tin foil as a hat against mind-reading. Much more durable and comfortable.
Yes, Soviet engineers were less cautious with nuclear reactors, and they got serious accidents, in submarines among others. And for radioactivity coming from coal: In Europe, fumes are filtered away at power plants exhausts for 30 years. You should obtain it from your government if you believe they're radioactive.
Waterboarding is a means of terrorizing people. Torture doesn't serve to get information.
Any reasoning like "if they head this, they wouldn't do that" is useless because you don't know why other people decide something.
QUOTE (wcelliott+Mar 9 2008, 11:34 AM)
I worked on the SM-3/KW program for about a year. They don't need a warhead, the kinetic energy of the closing velocities make the energy density greater than you get from high-explosives. Cheese would indeed be as effective at destroying a target with the closing speeds we're talking about.
I've seen the test results (videos) of the targets getting hit by the SM-3/KW, and the term "debris" truly misses the point, the targets turn into clouds of incandescent smoke.
BTW, a school-bus-sized satellite *would* be one of the smaller satellites launched these days.
And the satellites (especially the radar satellites) launched by the US wouldn't have the same need for high power as Russian/Soviet radar satellites. US radar technology is far more sophisticated than Russian radar technology, as is US solar cell technology. Those two facts, combined with the different political systems and cultural differences account for the fact that the vast majority of reactors in-orbit these days are Soviet-built. The Soviets required their high school students to study a lot more physics than American high school students do, and a lot less time on "Gaia"-type BS. Soviet radars *needed* more energy, and Soviet engineers were a lot less frightened by nuclear energy (over-hyped by Western Greenpeace-types), because advanced radars require advanced computers, and their chip technology isn't as advanced as ours. Neither is their solar cell technology, so getting the same power would require lots bigger solar panels, and they'd need lots more power to run their radars than we need.
If you're worried about radiation, you really should be more concerned about coal-powered electrical power plants. They emit a lot more radioactive isotopes into the air than nuclear power plants or nuclear-powered satellites.
I, personally, would be more worried about the hydrazine, which is pretty much what they said at the time.
And target missiles are a lot cheaper and easier to control for testing SM-3/KW than spy satellites.
And, BTW, *nobody* has ever even gotten close to being able to read anybody's minds by any means, regardless of whatever imagery you've seen or BS you've read. The brain is FAR too complex for some MRI-type device to even be useful as a lie-detector (something that should be far simpler than "reading minds") which are used routinely in the intelligence industry to catch people who've started selling secrets or have changed sides. And they haven't been very successful at that, and that's with the person strapped-in and hooked-up to various sensors. And, if you could actually *read* someone's mind, why would you bother waterboarding captured terrorists?
And if you could *read* someone's mind from a distance, you wouldn't need to have air passengers take their shoes off and get frisked.
And if *satellites* could "read" minds, we would be having a lot more luck finding Al Qaida terrorists and Iraqi insurgents, wouldn't you think?
So you can put away your tin-foil hats, folks. Satellites can't read minds. (I wish they could.)
First off, I have no idea how "mind reading" satellites entered this debate. I do, however, understand the use of re-association as an effective propaganda tool; where one idea is associated to another in order to bring discredit upon the later.
A review of the first post clearly indicates that the issue is whether the satellite may have used nuclear power as a power source for the radars.
The quoted post, directly above, was informative by conveying the fact that our technology and sensors are indeed, orders of magnitude more advanced than the Soviet Era technology responsible for most of the nuclear powered systems now in orbit.
It appears that most of power packs used by the Soviet era RORSATS functioned as designed at life cycle end; that is, the power packs separated and boosted to the burial orbits.
Since this is a physics board, instead of basing our arguments on personal attack or re-assigned association; could we look at the physics of orbits, micro-wave attenuation, solar insolation, photovoltaic efficiencies, and the other scientifically defined topics related to the issue?
I think it would be helpful if we begin with the physics of orbiting satellites, to determine what other advantages there may be in using power packs instead of solar arrays for high power application. Perhaps we could begin by the mathematical definition of orbital decay as a function of "ballistic coefficient," semi-major axis, and eccentricity.
Gavilan
I've seen the test results (videos) of the targets getting hit by the SM-3/KW, and the term "debris" truly misses the point, the targets turn into clouds of incandescent smoke.
BTW, a school-bus-sized satellite *would* be one of the smaller satellites launched these days.
And the satellites (especially the radar satellites) launched by the US wouldn't have the same need for high power as Russian/Soviet radar satellites. US radar technology is far more sophisticated than Russian radar technology, as is US solar cell technology. Those two facts, combined with the different political systems and cultural differences account for the fact that the vast majority of reactors in-orbit these days are Soviet-built. The Soviets required their high school students to study a lot more physics than American high school students do, and a lot less time on "Gaia"-type BS. Soviet radars *needed* more energy, and Soviet engineers were a lot less frightened by nuclear energy (over-hyped by Western Greenpeace-types), because advanced radars require advanced computers, and their chip technology isn't as advanced as ours. Neither is their solar cell technology, so getting the same power would require lots bigger solar panels, and they'd need lots more power to run their radars than we need.
If you're worried about radiation, you really should be more concerned about coal-powered electrical power plants. They emit a lot more radioactive isotopes into the air than nuclear power plants or nuclear-powered satellites.
I, personally, would be more worried about the hydrazine, which is pretty much what they said at the time.
And target missiles are a lot cheaper and easier to control for testing SM-3/KW than spy satellites.
And, BTW, *nobody* has ever even gotten close to being able to read anybody's minds by any means, regardless of whatever imagery you've seen or BS you've read. The brain is FAR too complex for some MRI-type device to even be useful as a lie-detector (something that should be far simpler than "reading minds") which are used routinely in the intelligence industry to catch people who've started selling secrets or have changed sides. And they haven't been very successful at that, and that's with the person strapped-in and hooked-up to various sensors. And, if you could actually *read* someone's mind, why would you bother waterboarding captured terrorists?
And if you could *read* someone's mind from a distance, you wouldn't need to have air passengers take their shoes off and get frisked.
And if *satellites* could "read" minds, we would be having a lot more luck finding Al Qaida terrorists and Iraqi insurgents, wouldn't you think?
So you can put away your tin-foil hats, folks. Satellites can't read minds. (I wish they could.)
First off, I have no idea how "mind reading" satellites entered this debate. I do, however, understand the use of re-association as an effective propaganda tool; where one idea is associated to another in order to bring discredit upon the later.
A review of the first post clearly indicates that the issue is whether the satellite may have used nuclear power as a power source for the radars.
The quoted post, directly above, was informative by conveying the fact that our technology and sensors are indeed, orders of magnitude more advanced than the Soviet Era technology responsible for most of the nuclear powered systems now in orbit.
It appears that most of power packs used by the Soviet era RORSATS functioned as designed at life cycle end; that is, the power packs separated and boosted to the burial orbits.
Since this is a physics board, instead of basing our arguments on personal attack or re-assigned association; could we look at the physics of orbits, micro-wave attenuation, solar insolation, photovoltaic efficiencies, and the other scientifically defined topics related to the issue?
I think it would be helpful if we begin with the physics of orbiting satellites, to determine what other advantages there may be in using power packs instead of solar arrays for high power application. Perhaps we could begin by the mathematical definition of orbital decay as a function of "ballistic coefficient," semi-major axis, and eccentricity.
Gavilan
The mathematical definition of orbital decay would be very useful if only it could help making some kind of prediction... Which isn't within the state of the art today. Hey, if you can achieve this, it will be an improvement!
Soviet era technology shouldn't be underestimated, even for radars. Remember the Mig-31 had a synthetic aperture radar before many competitors. Even better, they could couple the radars of several Mig-31 in formation flight to improve the performances, something competitors (especially Dassault +Thomson) tried hard but failed to achieve.
Another example is the Soyuz (or rather Semiorka) rocket, which is still among the best ones after >40 years.
As for choosing a nuclear reactor rather than photovoltaic cells, so many reasons have nothing to do with technology or physics... How could you argue somebody else decided this or that because you believe it's better? They took reactors because some Party member said it's good stuff that shows superiority over Western technology. I would chose solar panels even if they were worse because they're cleaner.
And if any single one of the thousand space engineers had assembled a solar panel by himself, we would have had solar thermal generators for decades. Believe me: I assembled about 0.2m2, so I know assembling 10m2 is completely insane. Just an example of an extremely bad engineering choice - but intellectual arguments won't let you notice it.
About US-193: Why do you all pretend it to be a radar observation satellite? I have read absolutely nothing serious about it, only rumours and unsubstantiated posts. As far as I know, the military said "a military satellite" and that's all. It can have been a weapon just as well, for instance.
And could anybody tell why the hell should there have been hydrazine (N2H4) onboard, instead of the modern MMH or UDMH combined with N2O4? N2H4 is outfashioned for decades now.
Soviet era technology shouldn't be underestimated, even for radars. Remember the Mig-31 had a synthetic aperture radar before many competitors. Even better, they could couple the radars of several Mig-31 in formation flight to improve the performances, something competitors (especially Dassault +Thomson) tried hard but failed to achieve.
Another example is the Soyuz (or rather Semiorka) rocket, which is still among the best ones after >40 years.
As for choosing a nuclear reactor rather than photovoltaic cells, so many reasons have nothing to do with technology or physics... How could you argue somebody else decided this or that because you believe it's better? They took reactors because some Party member said it's good stuff that shows superiority over Western technology. I would chose solar panels even if they were worse because they're cleaner.
And if any single one of the thousand space engineers had assembled a solar panel by himself, we would have had solar thermal generators for decades. Believe me: I assembled about 0.2m2, so I know assembling 10m2 is completely insane. Just an example of an extremely bad engineering choice - but intellectual arguments won't let you notice it.
About US-193: Why do you all pretend it to be a radar observation satellite? I have read absolutely nothing serious about it, only rumours and unsubstantiated posts. As far as I know, the military said "a military satellite" and that's all. It can have been a weapon just as well, for instance.
And could anybody tell why the hell should there have been hydrazine (N2H4) onboard, instead of the modern MMH or UDMH combined with N2O4? N2H4 is outfashioned for decades now.
QUOTE (Enthalpy+Mar 9 2008, 07:09 PM)
About US-193: Why do you all pretend it to be a radar observation satellite? I have read absolutely nothing serious about it, only rumours and unsubstantiated posts. As far as I know, the military said "a military satellite" and that's all. It can have been a weapon just as well, for instance.
And could anybody tell why the hell should there have been hydrazine (N2H4) onboard, instead of the modern MMH or UDMH combined with N2O4? N2H4 is outfashioned for decades now.
No it couldn't be a weapon.
The reason being, the ONLY logical weapon to put into orbit would be a nuclear weapon (otherwise the amount of explosive power is certainly not worth the expense), but if you hit a nuclear weapon with a KE projectile at 20,000+ mph, then you would detect the fallout from the nuclear material all over the globe as it re-entered (re-entry would do nothing to reduce the radioactivity of the material that made up the bomb).
Didn't happen.
One reason I can see for using Hydrazine is that, unlike MMH and UDMH, its a monopropellent and thus is a much simpler (and thus a more reliable system) than any system that involves both a propellent and an oxidizer (even if they are hypergolic) and reliability is a plus for a propulsion system that needs to be functional for many years.
Arthur
And could anybody tell why the hell should there have been hydrazine (N2H4) onboard, instead of the modern MMH or UDMH combined with N2O4? N2H4 is outfashioned for decades now.
No it couldn't be a weapon.
The reason being, the ONLY logical weapon to put into orbit would be a nuclear weapon (otherwise the amount of explosive power is certainly not worth the expense), but if you hit a nuclear weapon with a KE projectile at 20,000+ mph, then you would detect the fallout from the nuclear material all over the globe as it re-entered (re-entry would do nothing to reduce the radioactivity of the material that made up the bomb).
Didn't happen.
One reason I can see for using Hydrazine is that, unlike MMH and UDMH, its a monopropellent and thus is a much simpler (and thus a more reliable system) than any system that involves both a propellent and an oxidizer (even if they are hypergolic) and reliability is a plus for a propulsion system that needs to be functional for many years.
Arthur
I'm extremely wary of assertions like "it can only be of that kind"... This generally underestimates other people's imagination. A bit like when one single person thinks for a full hour and tells "old Egyptians built pyramids that way" or "couldn't build them" - while thousands of brilliant people then thought for centuries to find adequate technology.
Not all weapons are bombs. For instance, the Airborne Laser System (ABL) isn't a bomb, but is quite efficient, and steering its light would be easier from a satellite than from a plane, as the light would cross less air.
OK, the ABL needs a full Jumbo length, so it wouldn't fit in a satellite as is. But it's an example of weapon type a satellite may carry.
Sure, we would have detected uranium or plutonium. And fusion bombs without U nor Pu still don't exist, as far as I know - though the Z-machine certainly is a step in this direction. Anyway, I see no good reason to put a nuclear bomb in a satellite, as a plane or missile (or an elevator) is a better vector for it, even if an EMP was wanted.
Hydrazine :
I certainly agree it's justified only as a simpler and hence more reliable monopropellant. The point is that any satellite needs reliability, and all satellites to my knowledge switched to UDMH or MMH/N2O4, as this technology is now mature and more efficient. Even better, the -60°C or -70°C freezing point in fact improves reliability quite a lot.
In fact, I can't remember having seen for decades a description of an industrial satellite using monopropellant N2H4.
My guess is that MMH or UDMH was once again called "hydrazine" a bit improperly. Which doesn't make it less toxic, cough cough.
Not all weapons are bombs. For instance, the Airborne Laser System (ABL) isn't a bomb, but is quite efficient, and steering its light would be easier from a satellite than from a plane, as the light would cross less air.
OK, the ABL needs a full Jumbo length, so it wouldn't fit in a satellite as is. But it's an example of weapon type a satellite may carry.
Sure, we would have detected uranium or plutonium. And fusion bombs without U nor Pu still don't exist, as far as I know - though the Z-machine certainly is a step in this direction. Anyway, I see no good reason to put a nuclear bomb in a satellite, as a plane or missile (or an elevator) is a better vector for it, even if an EMP was wanted.
Hydrazine :
I certainly agree it's justified only as a simpler and hence more reliable monopropellant. The point is that any satellite needs reliability, and all satellites to my knowledge switched to UDMH or MMH/N2O4, as this technology is now mature and more efficient. Even better, the -60°C or -70°C freezing point in fact improves reliability quite a lot.
In fact, I can't remember having seen for decades a description of an industrial satellite using monopropellant N2H4.
My guess is that MMH or UDMH was once again called "hydrazine" a bit improperly. Which doesn't make it less toxic, cough cough.
Shoot Spy Satellite, a new power show to the others, May the world more peaceful.
May God save us!
AMon!
May God save us!
AMon!
Just a short word about mind-reading MRI, though not completely in-topic:
http://www.nature.com/nature/journal/vaop/...ature06713.html
by chance, Nature publishes a paper these days.
Reading by MRI the image currently observed by the brains.
Not even completely new.
Comparable results already exist for brain's areas controlling muscles or building sentences or speaking sounds out.
Thinking to these actions or remembering them also give distinctive patterns.
Sorry for the interruption.
http://www.nature.com/nature/journal/vaop/...ature06713.html
by chance, Nature publishes a paper these days.
Reading by MRI the image currently observed by the brains.
Not even completely new.
Comparable results already exist for brain's areas controlling muscles or building sentences or speaking sounds out.
Thinking to these actions or remembering them also give distinctive patterns.
Sorry for the interruption.
Equating what is in that article to MIND READING is quite a STRETCH.
Arthur
Arthur
It just tells once again that pictures of brain activity allow to infer the activity. Not necessarily the most impressive result, I just fell on it yesterday.
I read papers several years ago where observers could tell what phalanx of what finger the testperson was planning to move. Far more convincing.
Don't forget that the imaging technology used in mind-reading machines isn't MRI. Pictures of the activity may be better, though this certainly isn't easy.
Making pictures is only a part of the task. To analyze them, you need programmes able to learn the "map" of each target person's brain. Not completely easy now, certainly difficult decades ago.
But for such a perverse activity, no difficulty is too big...
I read papers several years ago where observers could tell what phalanx of what finger the testperson was planning to move. Far more convincing.
Don't forget that the imaging technology used in mind-reading machines isn't MRI. Pictures of the activity may be better, though this certainly isn't easy.
Making pictures is only a part of the task. To analyze them, you need programmes able to learn the "map" of each target person's brain. Not completely easy now, certainly difficult decades ago.
But for such a perverse activity, no difficulty is too big...
Still, nothing you are describing is anywhere near the concept of MIND READING, as in knowing what someone is thinking.
And FYI, there is no way that MRI technology as it now exists could do so.
It takes several minutes to get just one brain scan.
And even then its done in slices, so there is never one picture of the brain at one instant in time.
Consider how much you can think of in 2 minutes.
Arthur
And FYI, there is no way that MRI technology as it now exists could do so.
It takes several minutes to get just one brain scan.
And even then its done in slices, so there is never one picture of the brain at one instant in time.
Consider how much you can think of in 2 minutes.
Arthur
Enthalpy stated- "The mathematical definition of orbital decay would be very useful if only it could help making some kind of prediction... Which isn't within the state of the art today. Hey, if you can achieve this, it will be an improvement!
My reply - See page 64 of "Space Craft Attitude Determination and Control" - Ed. by James R. Wertz. 1985. Clearly defined as a funciton of ballistic coefficient, earths gravitational parameter, perigee hight, and eccentricity.
adoucette stated - "then you would detect the fallout from the nuclear material all over the globe as it re-entered (re-entry would do nothing to reduce the radioactivity."
My reply - There is another advantage to high altitude dispersal; in our modern environment, depending on the specific activity of the nuclide, such dispersal increases the amount of material mass required to raise the background level high enough to trigger alarm. Although, the term "back ground radiation level" is often used as smoke and mirrors to minimize concern during accidental releases, it is also the metric that would trigger further environmental focus if an increase was detected.
I don't know what type of power source the primary radars had. But in its current state it is safe to assume that regardless of what may be detected in the future, it will be nearly impossible to connect it to this satellite.
Gavilan
My reply - See page 64 of "Space Craft Attitude Determination and Control" - Ed. by James R. Wertz. 1985. Clearly defined as a funciton of ballistic coefficient, earths gravitational parameter, perigee hight, and eccentricity.
adoucette stated - "then you would detect the fallout from the nuclear material all over the globe as it re-entered (re-entry would do nothing to reduce the radioactivity."
My reply - There is another advantage to high altitude dispersal; in our modern environment, depending on the specific activity of the nuclide, such dispersal increases the amount of material mass required to raise the background level high enough to trigger alarm. Although, the term "back ground radiation level" is often used as smoke and mirrors to minimize concern during accidental releases, it is also the metric that would trigger further environmental focus if an increase was detected.
I don't know what type of power source the primary radars had. But in its current state it is safe to assume that regardless of what may be detected in the future, it will be nearly impossible to connect it to this satellite.
Gavilan
QUOTE (Gavilan+Mar 15 2008, 12:41 AM)
adoucette stated - "then you would detect the fallout from the nuclear material all over the globe as it re-entered (re-entry would do nothing to reduce the radioactivity."
My reply - There is another advantage to high altitude dispersal; in our modern environment, depending on the specific activity of the nuclide, such dispersal increases the amount of material mass required to raise the background level high enough to trigger alarm. Although, the term "back ground radiation level" is often used as smoke and mirrors to minimize concern during accidental releases, it is also the metric that would trigger further environmental focus if an increase was detected.
By definition, any nuclear power source, to produce a reasonable amount of power in a relatively short time frame, has to be quite radioactive. That's why RTGs use the much shorter half life PU 239 to generate heat.
The net is, any power source would contain a significant amount of radioactive material and considering the MANY international monitoring stations for radioactivity there is NO WAY that an atmospheric release of nuclear material would go undetected.
This is done via "sniffers" which, by filtering large quantities of air, quickly detect increases in the background radiation in the material trapped in the filter. They work even at incredibly low levels of even DISTANT releases of radiation.
The detection of an increase in background radiation though has NOT been reported following the shoot down.
Thus there was no significant radiation source on that satellite.
Arthur
My reply - There is another advantage to high altitude dispersal; in our modern environment, depending on the specific activity of the nuclide, such dispersal increases the amount of material mass required to raise the background level high enough to trigger alarm. Although, the term "back ground radiation level" is often used as smoke and mirrors to minimize concern during accidental releases, it is also the metric that would trigger further environmental focus if an increase was detected.
By definition, any nuclear power source, to produce a reasonable amount of power in a relatively short time frame, has to be quite radioactive. That's why RTGs use the much shorter half life PU 239 to generate heat.
The net is, any power source would contain a significant amount of radioactive material and considering the MANY international monitoring stations for radioactivity there is NO WAY that an atmospheric release of nuclear material would go undetected.
This is done via "sniffers" which, by filtering large quantities of air, quickly detect increases in the background radiation in the material trapped in the filter. They work even at incredibly low levels of even DISTANT releases of radiation.
The detection of an increase in background radiation though has NOT been reported following the shoot down.
Thus there was no significant radiation source on that satellite.
Arthur
Mind-reading:
I don't believe a second the machines rely on MRI. Not only the delay prohibits it. They also work at some distance, which I believe to be impossible with MRI. The limit could be about 10m, but making "observations" is very difficult as it needs to know where I was and where nearest people or objects were when I thought to something that was repeated to me later.
Also, I observed mind-reading to work in a train or in a car, but never in an airliner. Because the machines would be detected at boarding screening?
Satellite drag: forget any forecast. If an author gives a formula for that, it only proves he never tried a calculation on a real case, and belongs to the category of authors and teachers who believe Nature conforms to their theories just because they ignore experimental data. Not uncommon at all.
Look, I had the case some years ago with frequency filters. Books and teachers give circuits of active cells with two op amps which shall compensate each other's limited bandwidth. Pity, all of these cells just oscillate. Authors had just copied junk on another.
RTG: they commonly use the decades-lived Pu-238, not the fissile Pu-239.
Why should the satellite have been a radar satellite? I've seen no credible source for that allegation. The only direct source I've heard (the military speaker) said "a military satellite" and nothing more specific.
I don't believe a second the machines rely on MRI. Not only the delay prohibits it. They also work at some distance, which I believe to be impossible with MRI. The limit could be about 10m, but making "observations" is very difficult as it needs to know where I was and where nearest people or objects were when I thought to something that was repeated to me later.
Also, I observed mind-reading to work in a train or in a car, but never in an airliner. Because the machines would be detected at boarding screening?
Satellite drag: forget any forecast. If an author gives a formula for that, it only proves he never tried a calculation on a real case, and belongs to the category of authors and teachers who believe Nature conforms to their theories just because they ignore experimental data. Not uncommon at all.
Look, I had the case some years ago with frequency filters. Books and teachers give circuits of active cells with two op amps which shall compensate each other's limited bandwidth. Pity, all of these cells just oscillate. Authors had just copied junk on another.
RTG: they commonly use the decades-lived Pu-238, not the fissile Pu-239.
Why should the satellite have been a radar satellite? I've seen no credible source for that allegation. The only direct source I've heard (the military speaker) said "a military satellite" and nothing more specific.
A paper that supports Raman imaging of deep (how deep?) tissue:
http://www.sciencedaily.com/releases/2008/...80331172528.htm
This supports my explanation attempt that mind-reading may rely on Raman imaging to get pictures of the brain's activity quickly and from some distance. Another explanation attempt being imaging radars, but the necessary image resolution would be difficult to attain.
http://www.sciencedaily.com/releases/2008/...80331172528.htm
This supports my explanation attempt that mind-reading may rely on Raman imaging to get pictures of the brain's activity quickly and from some distance. Another explanation attempt being imaging radars, but the necessary image resolution would be difficult to attain.
QUOTE (Enthalpy+Apr 2 2008, 06:14 PM)
A paper that supports Raman imaging of deep (how deep?) tissue:
http://www.sciencedaily.com/releases/2008/...80331172528.htm
This supports my explanation attempt that mind-reading may rely on Raman imaging to get pictures of the brain's activity quickly and from some distance. Another explanation attempt being imaging radars, but the necessary image resolution would be difficult to attain.
No it doesn't.
First of all it requires using tiny nanoparticles injected into the body to serve as beacons.
Second of all it requires you to shine a laser on to those particles.
You can't shine a laser through a skull.
Arthur
http://www.sciencedaily.com/releases/2008/...80331172528.htm
This supports my explanation attempt that mind-reading may rely on Raman imaging to get pictures of the brain's activity quickly and from some distance. Another explanation attempt being imaging radars, but the necessary image resolution would be difficult to attain.
No it doesn't.
First of all it requires using tiny nanoparticles injected into the body to serve as beacons.
Second of all it requires you to shine a laser on to those particles.
You can't shine a laser through a skull.
Arthur
Please pardon my intrusion into this thread without reading all the posts, but the ones I've read have so many fallacies that I feel the need to intervene.
I can't say with absolute certainty that RTGs (radioactive "batteries") haven't been used on any US satellites for decades, but the company I work for makes them, and I've worked with JPL, and JPL is the only US customer that I know of who considers using them, and then *only* for deep-space probes. If it's in earth's orbit (or closer to the sun than earth's orbit), it's powered by photoelectric cells for the very simple reason that no one wants this sort of publicity/ embarrassment when the spacecraft re-enters the earth's atmosphere or fails to achieve a stable long-term orbit. (We built the Space Station's photoelectric "wings", too.)
The more likely causes of concern, should a spy satellite re-enter uncontrolled and/or over a populated area are (in no particular order), the falling of classified US technology into other countries' hands (which might provide them with information useful to them if they chose to retro-engineer our capabilities so that they could build spy satellites of their own with capabilities equal to ours or learn enough from intact debris to jam/disable our other spy satellites), or the direct damage, physical and political, caused by tanks of toxic propellants, used to divert the spy satellites to more interesting orbits, falling on or near populated areas. One such propellant commonly used in spacecraft is hydrazine, which pretty much embodies every meaning of the term "nasty", other than what you'd want in a blind date with a hot model. Directly toxic, corrosive, carcinogenic in microscopic concentrations, and capable of making concrete burn, for instance. And spy satellites tend to last only as long as their propellant tanks, so those tanks tend to be pretty big, and therefore more likely to withstand at least the early parts of deorbit, so could conceivably drop their load over a city (or a reservoir) which could lead to disastrous consequences. Think Chernobyl, and multiply by 10,000x.
If one of those deorbited over Beijing or Moscow (or London or Paris)...
If it were your call to make, would you risk an uncontrolled reentry, or would you vaporize it? (All adults here should have the same answer.)
Now, as for "reading minds", it can't be done in an MRI unit under controlled circumstances, regardless of what you might've heard or read (newspaper reporters seldom understand the content of the technical articles they write, and always look for the most sensational interpretations to increase their papers' sales). The brain works too subtly to be "read" by anything ever built by man. Only God can read a person's mind, and I'm not even sure whether he does or doesn't - He went through a lot of bother making this universe so that Free Will could exist (it took two sets of physics, compatible but fundamentally different to allow us to have Free Will and reading minds could conceivably subvert the intent of His own creation). Your behavior can be governed by the output of a single neural synapse, and you have 10^10th neurons and each has something like 10,000 synapses. It's been shown in brain research for instance that some very familiar faces are recognized by a single dedicated neuron. Do you really think that any machine ever built could sense the state of 10^14th synapses? Even if someone *could* read the state of all those synapses, you'd need the map of how each of them is interconnected, and *then* determine what each neuron's function is. (Please, tell me how you'd go about doing that.)
And you figure it could be done from orbit?
No, it can't.
Period.
Anybody tells you different, don't engage, don't make eye contact, just back away slowly and exit as quickly as you can.
I can't say with absolute certainty that RTGs (radioactive "batteries") haven't been used on any US satellites for decades, but the company I work for makes them, and I've worked with JPL, and JPL is the only US customer that I know of who considers using them, and then *only* for deep-space probes. If it's in earth's orbit (or closer to the sun than earth's orbit), it's powered by photoelectric cells for the very simple reason that no one wants this sort of publicity/ embarrassment when the spacecraft re-enters the earth's atmosphere or fails to achieve a stable long-term orbit. (We built the Space Station's photoelectric "wings", too.)
The more likely causes of concern, should a spy satellite re-enter uncontrolled and/or over a populated area are (in no particular order), the falling of classified US technology into other countries' hands (which might provide them with information useful to them if they chose to retro-engineer our capabilities so that they could build spy satellites of their own with capabilities equal to ours or learn enough from intact debris to jam/disable our other spy satellites), or the direct damage, physical and political, caused by tanks of toxic propellants, used to divert the spy satellites to more interesting orbits, falling on or near populated areas. One such propellant commonly used in spacecraft is hydrazine, which pretty much embodies every meaning of the term "nasty", other than what you'd want in a blind date with a hot model. Directly toxic, corrosive, carcinogenic in microscopic concentrations, and capable of making concrete burn, for instance. And spy satellites tend to last only as long as their propellant tanks, so those tanks tend to be pretty big, and therefore more likely to withstand at least the early parts of deorbit, so could conceivably drop their load over a city (or a reservoir) which could lead to disastrous consequences. Think Chernobyl, and multiply by 10,000x.
If one of those deorbited over Beijing or Moscow (or London or Paris)...
If it were your call to make, would you risk an uncontrolled reentry, or would you vaporize it? (All adults here should have the same answer.)
Now, as for "reading minds", it can't be done in an MRI unit under controlled circumstances, regardless of what you might've heard or read (newspaper reporters seldom understand the content of the technical articles they write, and always look for the most sensational interpretations to increase their papers' sales). The brain works too subtly to be "read" by anything ever built by man. Only God can read a person's mind, and I'm not even sure whether he does or doesn't - He went through a lot of bother making this universe so that Free Will could exist (it took two sets of physics, compatible but fundamentally different to allow us to have Free Will and reading minds could conceivably subvert the intent of His own creation). Your behavior can be governed by the output of a single neural synapse, and you have 10^10th neurons and each has something like 10,000 synapses. It's been shown in brain research for instance that some very familiar faces are recognized by a single dedicated neuron. Do you really think that any machine ever built could sense the state of 10^14th synapses? Even if someone *could* read the state of all those synapses, you'd need the map of how each of them is interconnected, and *then* determine what each neuron's function is. (Please, tell me how you'd go about doing that.)
And you figure it could be done from orbit?
No, it can't.
Period.
Anybody tells you different, don't engage, don't make eye contact, just back away slowly and exit as quickly as you can.
O yes, Arthur, laser light does go through a skull, as I've already checked. The best wavelength is far infrared. You lose some 30dB (3 optical densities) at each pass, and Raman is a big advantage here as the return signal has a different frequency from the transmitted one, allowing filters to discriminate both. Using adequate angles also helps to target only deep tissues.
Going twice through the skull in infrared and making meanwhile a lossy reflection is proved by a handheld device developed in India for rescuers to observe if a victim's brain gets blood properly.
Anyway, if you find a skull or a thick bone, but it between a lamp and your eyes, and you will see light through it, even at visible wavelengths.
Going twice through the skull in infrared and making meanwhile a lossy reflection is proved by a handheld device developed in India for rescuers to observe if a victim's brain gets blood properly.
Anyway, if you find a skull or a thick bone, but it between a lamp and your eyes, and you will see light through it, even at visible wavelengths.