I've been away for awhile, someone may have brought this up already. Anyone got any ideas about this? Could this be the same anomaly that puzzles big bang theorists?
http://www.msnbc.msn.com/id/23410705/
Perhaps .9r does not = 1 
I saw this yesterday and started to post it too.
I saw this yesterday and started to post it too.
Frustrating reading a fluffy dumbed-down article. It would be interesting to see what they had correctly considered. This kinda smells like they decided some known effect was negligible, but was really not negligible, like some subtle effects of GR, temperature & composition of ionosphere, solar wind variations (i.e. whether the spacecraft traveled through an ion stream following the Earths magnetic field), variations in the Earth's gravity between equator and poles, variations in crust composition and thus gravity, the charge on the spacecraft and how it is affected by the Earth's magnetic field, etc.. For interplanetary space, there's the composition of incoming and outgoing solar winds, maybe even dust from recent cometary activity.
It's perfectly possible that a known effect was mistakenly considered negligible. Though, I trust the many guys who checked it not to have been mistaken by the elementary effects you mention.
Or it is something unknown up to now. Of course, people relate it to the abnormal motions of galaxies etc that fashionable theories attribute to dark matter.
As far as I know, it's still a puzzle. Maybe somebody comes with an explanation that fits the observed figures. Or rather, we observe another spacecraft that doesn't show this anomaly and realize that this one is out of the ecliptic plane, or flew during a solar minimum, or is denser, or never passed by Jupiter, or whatever it will be.
Or if we consider the puzzle is important enough, we send some dozens small spacecrafts just to observe this effect. With different masses, densities, maybe speeds and directions... This will clarify how the explanation should look like.
Very nice small experiment! Look, you build many small spacecrafts. Each could be very simple: a chemical primary battery, a thermal insulation, an transmitter, an antenna. No directional antenna [I'm probably wrong here, pity]. The spacecrafts transmit only once in a month, just a fixed sequence of 1 and 0 that allows to measure their distance and speed relative to Earth. Hopefully, big antennas on Earth and signal processing are enough to recover the fixed sequence.
You put all spacecrafts on the same rocket. As they are small, you make a direct shot at 30km/s, and they get away at 1 hour-light per year.
Then you compare the differences of distances to the spacecrafts and relate them to the properties of the crafts: lightweight vs heavy, big wings vs compact...
Or it is something unknown up to now. Of course, people relate it to the abnormal motions of galaxies etc that fashionable theories attribute to dark matter.
As far as I know, it's still a puzzle. Maybe somebody comes with an explanation that fits the observed figures. Or rather, we observe another spacecraft that doesn't show this anomaly and realize that this one is out of the ecliptic plane, or flew during a solar minimum, or is denser, or never passed by Jupiter, or whatever it will be.
Or if we consider the puzzle is important enough, we send some dozens small spacecrafts just to observe this effect. With different masses, densities, maybe speeds and directions... This will clarify how the explanation should look like.
Very nice small experiment! Look, you build many small spacecrafts. Each could be very simple: a chemical primary battery, a thermal insulation, an transmitter, an antenna. No directional antenna [I'm probably wrong here, pity]. The spacecrafts transmit only once in a month, just a fixed sequence of 1 and 0 that allows to measure their distance and speed relative to Earth. Hopefully, big antennas on Earth and signal processing are enough to recover the fixed sequence.
You put all spacecrafts on the same rocket. As they are small, you make a direct shot at 30km/s, and they get away at 1 hour-light per year.
Then you compare the differences of distances to the spacecrafts and relate them to the properties of the crafts: lightweight vs heavy, big wings vs compact...
The experiment looks better as I feared, especially for the radio transmissions. Really simple!
Put a reasonable lithium primary battery in each spacecraft (no solar panels, no RTG, no attitude control). 10MJ electricity (16mW * 20 years!), 25% of it for transmissions. Transmit 10 pings per month for 20 years, you have 1kJ per ping.
Receive them with the VLA (27 dishes of 25m sum to 1.3e4 m2), at 10 hours-light, you still get 9e-21 J per ping, or 20 times 30K or 60 times 10K.
=> No directional antenna needed on the spacecrafts! No attitude control!
The thermal design is relatively easy as well (accumulate the 1kJ heat produced by the transmitter, superinsulate everything). The crafts are so simple that an engineering school can design them.
Put a reasonable lithium primary battery in each spacecraft (no solar panels, no RTG, no attitude control). 10MJ electricity (16mW * 20 years!), 25% of it for transmissions. Transmit 10 pings per month for 20 years, you have 1kJ per ping.
Receive them with the VLA (27 dishes of 25m sum to 1.3e4 m2), at 10 hours-light, you still get 9e-21 J per ping, or 20 times 30K or 60 times 10K.
=> No directional antenna needed on the spacecrafts! No attitude control!
The thermal design is relatively easy as well (accumulate the 1kJ heat produced by the transmitter, superinsulate everything). The crafts are so simple that an engineering school can design them.
Now, a more refined measurement can be done.
If each spacecraft listens to the pings emitted by his neighbours and echoes them (with a known delay) to the Earth, we can know the relative positions of the crafts in 3D.
Still without directional antennas nor attitude control: At 600MHz (is this precise enough?), each spacecraft receives the pings on 0.02 m2. Needing an energy of 10* 100K from the transmitted 1kJ, this allows for a distance of 11 Gm or 37s-light. Not bad!
This time, signal-processing capability (deconvolving the sequence transmitted by the neighbours) is needed onboard. But with several mW mean power available, it looks possible.
So you put some 10 different crafts in your fast rocket, separate them all at 30km/s in no precise direction, and observe which one is more accelerated towards the Sun.
Don't forget to negotiate some VLA time before the launch.
It all looks incredibly simple.
Enough for now: Bed.
If each spacecraft listens to the pings emitted by his neighbours and echoes them (with a known delay) to the Earth, we can know the relative positions of the crafts in 3D.
Still without directional antennas nor attitude control: At 600MHz (is this precise enough?), each spacecraft receives the pings on 0.02 m2. Needing an energy of 10* 100K from the transmitted 1kJ, this allows for a distance of 11 Gm or 37s-light. Not bad!
This time, signal-processing capability (deconvolving the sequence transmitted by the neighbours) is needed onboard. But with several mW mean power available, it looks possible.
So you put some 10 different crafts in your fast rocket, separate them all at 30km/s in no precise direction, and observe which one is more accelerated towards the Sun.
Don't forget to negotiate some VLA time before the launch.
It all looks incredibly simple.
Enough for now: Bed.
Secret services are just a hopeless bunch of morons. The description of the spacecrafts is here in the thread, accessible to anybody, but they nevertheless entered my computer. They just can't help.
Bande de crétins.
Bande de crétins.
The thermal design is less obvious than I hoped.
If the spacecrafts go no farther from the Sun than Jupiter (and nearer would be better!), one may design them to get their warmth from the sunlight, but this isn't easy.
The other option, especially if going farther, is to insulate the spacecraft and rely on the battery's power to keep the craft warm. However, it needs an excellent insulation. Here it goes.
Take a 15kg spacecraft (remember we want to launch one or two dozens of them, possibly at 30km/s). Of this mass, 11kg will be a Li-SOCl2 primary battery that brings 22MJ. Over 10 years, 72mW mean power are available, of which 18mW (mean) will be radiated as the radio signal, 18mW lost in the transmitter and 36mW used by onboard electronics, especially processing the signal from the neighbour crafts.
This equates to 10 pings a month, of 4700J each. And 54mW heat the spacecraft - this is minute. The whole craft must be wrapped in multilayer insulation.
First, the antennas must be within the spacecraft's insulation, because there's no simple way to bring the signal outside without losing too much heat. To prevent the multilayer insulation from screening the radio signal, its metal layer must be interrupted from place to place - for the same reason a transformer's core is layered. In fact, the metal islands must be quite smaller than half a wavelength, so that even the stray capacitance between adjacent layers doesn't make a short circuit that would screen the signal. For the multilayer insulation to work, the cuts in the metal layers must be offset from one layer to another. And the antennas may best be so-called patch ones.
Then, fastening the spacecraft to the launcher needs a trick, as no part can go through the multilayer insulation. The idea is to have some sort of self-healing MLI: During launch (near warm Earth orbit), fastening parts join the spacecraft to the launcher, but these pieces (I like screws combined with electric motors and gears) stay with the launcher at separation, and the MLI closes the feedthrough as the fastening pieces are gone.
One possibility is a flat piece of MLI whose layers are cut increasingly wide, corresponding to the static MLI increasingly narrow, so that the cuts don't overlap. The flat piece may move by its spring effect, or rather be tied to a hatch moved by a spring. Another possibility is to make a hose of MLI around the fastening parts and have an elastic clamp close the hose as the fastening parts are gone.
The craft being a cube of 0.3m edge length, the MLI needs about 100 plies.
Some active thermal control is probably desireable, it could be done by opening a small portion of the MLI with an electric motor or by the thermal dilation of an adequate device.
Really simple!
If the spacecrafts go no farther from the Sun than Jupiter (and nearer would be better!), one may design them to get their warmth from the sunlight, but this isn't easy.
The other option, especially if going farther, is to insulate the spacecraft and rely on the battery's power to keep the craft warm. However, it needs an excellent insulation. Here it goes.
Take a 15kg spacecraft (remember we want to launch one or two dozens of them, possibly at 30km/s). Of this mass, 11kg will be a Li-SOCl2 primary battery that brings 22MJ. Over 10 years, 72mW mean power are available, of which 18mW (mean) will be radiated as the radio signal, 18mW lost in the transmitter and 36mW used by onboard electronics, especially processing the signal from the neighbour crafts.
This equates to 10 pings a month, of 4700J each. And 54mW heat the spacecraft - this is minute. The whole craft must be wrapped in multilayer insulation.
First, the antennas must be within the spacecraft's insulation, because there's no simple way to bring the signal outside without losing too much heat. To prevent the multilayer insulation from screening the radio signal, its metal layer must be interrupted from place to place - for the same reason a transformer's core is layered. In fact, the metal islands must be quite smaller than half a wavelength, so that even the stray capacitance between adjacent layers doesn't make a short circuit that would screen the signal. For the multilayer insulation to work, the cuts in the metal layers must be offset from one layer to another. And the antennas may best be so-called patch ones.
Then, fastening the spacecraft to the launcher needs a trick, as no part can go through the multilayer insulation. The idea is to have some sort of self-healing MLI: During launch (near warm Earth orbit), fastening parts join the spacecraft to the launcher, but these pieces (I like screws combined with electric motors and gears) stay with the launcher at separation, and the MLI closes the feedthrough as the fastening pieces are gone.
One possibility is a flat piece of MLI whose layers are cut increasingly wide, corresponding to the static MLI increasingly narrow, so that the cuts don't overlap. The flat piece may move by its spring effect, or rather be tied to a hatch moved by a spring. Another possibility is to make a hose of MLI around the fastening parts and have an elastic clamp close the hose as the fastening parts are gone.
The craft being a cube of 0.3m edge length, the MLI needs about 100 plies.
Some active thermal control is probably desireable, it could be done by opening a small portion of the MLI with an electric motor or by the thermal dilation of an adequate device.
Really simple!
QUOTE
Really simple!
LOL
why don't you supply a mathematical proof of your guesswork
I saw a thread on this article in a different forum, and someone there made a comment about proving MoND, or Modified Newtonian Dynamics. I haven't had time to look into the papers about that yet.
I wonder if it's occured to anyone that the spacecraft may have simply picked up some "space-dust" along the way.
It would certainly slow them down, provided they picked up enough (moving through the kuiper belt, perhaps.)
It would certainly slow them down, provided they picked up enough (moving through the kuiper belt, perhaps.)
BDW, did you READ the article? 
It isn't a constant change in speed, it appears a force is giving them a small push towards the sun.
It isn't a constant change in speed, it appears a force is giving them a small push towards the sun.
QUOTE ("THEY"+Mar 6 2008, 05:24 PM)
BDW, did you READ the article?
It isn't a constant change in speed, it appears a force is giving them a small push towards the sun.
Yes, dear. I read it.
I understand, but if they were picking up more and more dust as they continued to travel... The kuiper belt would just have been where they got enough dust for us to notice it...
And the kuiper belt isn't the only pleace to pick up dust. The universe is full of it.
It isn't a constant change in speed, it appears a force is giving them a small push towards the sun.
Yes, dear. I read it.
I understand, but if they were picking up more and more dust as they continued to travel... The kuiper belt would just have been where they got enough dust for us to notice it...
And the kuiper belt isn't the only pleace to pick up dust. The universe is full of it.
I just realized something!
UBAVONTUBA IS RIGHT! BLACK HOLES ARE GOBBLING UP OUR SPACE SATELITTES, AND SOON, THE WORLD!
Or it could just be space dust.
UBAVONTUBA IS RIGHT! BLACK HOLES ARE GOBBLING UP OUR SPACE SATELITTES, AND SOON, THE WORLD!
Or it could just be space dust.
Actually, BDW, I withhold my arguement for now....... I read a different article last week, and I swear it said the force is noticed on both the space probes and the satelites orbiting earth. But I will have to search for the original article that I read, it wasn't the same as the link in this thread.
Got any rotten eggs you want to throw at me?
Got any rotten eggs you want to throw at me?
QUOTE ("THEY"+Mar 6 2008, 05:54 PM)
Actually, BDW, I withhold my arguement for now....... I read a different article last week, and I swear it said the force is noticed on both the space probes and the satelites orbiting earth. But I will have to search for the original article that I read, it wasn't the same as the link in this thread.
I'm not going to try to defend my "space-dust" theory too much, because it's just something I thought up off the top of my head, and I don't really have anything invested into it. Also, because I don't know enough technical information about the anomaly in question..
No, but I'll throw 10 dollar bills if you strip-dance for me
Just kidding. I'll throw flowers. No dancing needed.
User posted image: User posted image
I'm not going to try to defend my "space-dust" theory too much, because it's just something I thought up off the top of my head, and I don't really have anything invested into it. Also, because I don't know enough technical information about the anomaly in question..
QUOTE
Got any rotten eggs you want to throw at me?
No, but I'll throw 10 dollar bills if you strip-dance for me
Just kidding. I'll throw flowers. No dancing needed.
User posted image: User posted image
You guy's sigs are WAY too big....
Here is the original paper by Anderson et al:
http://arxiv.org/abs/gr-qc/0104064
It's well written, clear and easy to read, so I suggest everybody to read it.
It tells with simple words which explanations have been ruled out and why. This includes dust and gases, radiation pressure from the RTG emitting infrared, degassing from the RTG and the thrusters, and actually all sensible hypothesis.
Enjoy!
http://arxiv.org/abs/gr-qc/0104064
It's well written, clear and easy to read, so I suggest everybody to read it.
It tells with simple words which explanations have been ruled out and why. This includes dust and gases, radiation pressure from the RTG emitting infrared, degassing from the RTG and the thrusters, and actually all sensible hypothesis.
Enjoy!
Zarkov, the figures I put for the spacecrafts are no guesswork. I know to compute such properties for having already built a satellite.
People knowing the subject are capable of checking the figures I propose without further explanation and do realize it really is simple. And for those people who aren't able of checking them: Why should I give more explanations just for them? Their check wouldn't bring any sort of added certainty.
By the way, I don't need to write anything more than is in the post to make my calculations, and I expect other spacecraft engineers wouldn't write anything more neither, so this time would be badly invested.
People knowing the subject are capable of checking the figures I propose without further explanation and do realize it really is simple. And for those people who aren't able of checking them: Why should I give more explanations just for them? Their check wouldn't bring any sort of added certainty.
By the way, I don't need to write anything more than is in the post to make my calculations, and I expect other spacecraft engineers wouldn't write anything more neither, so this time would be badly invested.
Zarkov wouldn't understand any of your calculations anyway.
QUOTE (Enthalpy+Mar 6 2008, 08:32 PM)
Here is the original paper by Anderson et al:
http://arxiv.org/abs/gr-qc/0104064
It's well written, clear and easy to read, so I suggest everybody to read it.
It tells with simple words which explanations have been ruled out and why. This includes dust and gases, radiation pressure from the RTG emitting infrared, degassing from the RTG and the thrusters, and actually all sensible hypothesis.
Enjoy!
Oh well, so much for space dust.
Should I follow the example set so often on this forum and insist that I was right, regardless of any and all evidence to the contrary?
Or should I simply accept that I was wrong and move on...
Hmmm... Decisions, decisions.....
So how bout them Yankees, eh?
http://arxiv.org/abs/gr-qc/0104064
It's well written, clear and easy to read, so I suggest everybody to read it.
It tells with simple words which explanations have been ruled out and why. This includes dust and gases, radiation pressure from the RTG emitting infrared, degassing from the RTG and the thrusters, and actually all sensible hypothesis.
Enjoy!
Oh well, so much for space dust.
Should I follow the example set so often on this forum and insist that I was right, regardless of any and all evidence to the contrary?
Or should I simply accept that I was wrong and move on...
Hmmm... Decisions, decisions.....
So how bout them Yankees, eh?
Happily enough, I found the paper before writing myself "must be the thermal radiation from the RTG".
The guys at Anderson's team really have checked quite a couple of possibilities. And a serious discrepancy seems to stay. This is why people are excited about it, and consider launching specialized missions just for this purpose.
The guys at Anderson's team really have checked quite a couple of possibilities. And a serious discrepancy seems to stay. This is why people are excited about it, and consider launching specialized missions just for this purpose.
Hmmm, let me see.
What do we have in interaction here. Conductive materials? High velocities? Magnetic field (solar magnetic field).
What is electro-magnetic induction?
What is Lenz's law?
Duhhhhhh.
If only the Newton, Goddard, Tsiolkovsky, Oberth people would sit down and do a little joint study with the Maxwell, Gauss, Faraday, Weber people; perhaps they could better explain the simple stuff to the rest of us.
Never ask an expert to see a simple solution, it confuses the hell out of them.
Gavilan
What do we have in interaction here. Conductive materials? High velocities? Magnetic field (solar magnetic field).
What is electro-magnetic induction?
What is Lenz's law?
Duhhhhhh.
If only the Newton, Goddard, Tsiolkovsky, Oberth people would sit down and do a little joint study with the Maxwell, Gauss, Faraday, Weber people; perhaps they could better explain the simple stuff to the rest of us.
Never ask an expert to see a simple solution, it confuses the hell out of them.
Gavilan
Enthalpy
I have all the calculations
The Pioneer anomaly is caused by inertial field spin change+ at energy outputting Jupiter's distance and beyond...
This spin change is evident around Mars... which when Mars crashes against the Jupiter Bloch wall it shall break up as has the planet that is now the asteroid belt
the Earth will follow
The Earth satellite velocity changes are due to anisotropic field spin, and nothing to with inertial field spin changes....
There is a preferred "inertial orbital path" around a central body...... all others attract correctional forces (precession)
But I have decided this forum is typical of all forums... infested with vermin
and I am not going to waste my time here anymore.
I have all the calculations
The Pioneer anomaly is caused by inertial field spin change+ at energy outputting Jupiter's distance and beyond...
This spin change is evident around Mars... which when Mars crashes against the Jupiter Bloch wall it shall break up as has the planet that is now the asteroid belt
the Earth will follow
The Earth satellite velocity changes are due to anisotropic field spin, and nothing to with inertial field spin changes....
There is a preferred "inertial orbital path" around a central body...... all others attract correctional forces (precession)
But I have decided this forum is typical of all forums... infested with vermin
and I am not going to waste my time here anymore.
Zarkov doesn't have any calculations. And when he promises he's not going to waste any more time here, he's lying. This is one of the few forums that hasn't banned him, so he has little choice.
QUOTE (Gavilan+Mar 7 2008, 04:30 AM)
What do we have in interaction here. Conductive materials? High velocities? Magnetic field (solar magnetic field).
What is electro-magnetic induction?
What is Lenz's law?
Duhhhhhh.
What does high velocity have to do with anything? What's important for Lenz's law is the change in magnetic field. If one happens to be moving at high velocity through an unchanging magnetic field there will be no induced EMF. Conversely one could be holding still and if there is a changing magnetic field there will still be an EMF. It's better to leave velocity out of this discussion (I'd bet you're confusing Lenz's law with the Lorentz force).
Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly, as you can see here:
http://www.swpc.noaa.gov/ace/MAG_SWEPAM_2h.html
Lenz's law may imply a force on the spacecraft but the direction of this force is constantly changing and thus over time will average out to zero. The Sun's magnetic field is not a likely source.
What is electro-magnetic induction?
What is Lenz's law?
Duhhhhhh.
What does high velocity have to do with anything? What's important for Lenz's law is the change in magnetic field. If one happens to be moving at high velocity through an unchanging magnetic field there will be no induced EMF. Conversely one could be holding still and if there is a changing magnetic field there will still be an EMF. It's better to leave velocity out of this discussion (I'd bet you're confusing Lenz's law with the Lorentz force).
Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly, as you can see here:
http://www.swpc.noaa.gov/ace/MAG_SWEPAM_2h.html
Lenz's law may imply a force on the spacecraft but the direction of this force is constantly changing and thus over time will average out to zero. The Sun's magnetic field is not a likely source.
QUOTE
Lenz's law
yes it has all to do with Lenz's Law
Demonstrated well in Mercury's precessional orbit.
QUOTE (->
| QUOTE |
| Lenz's law |
yes it has all to do with Lenz's Law
Demonstrated well in Mercury's precessional orbit.
If only the Newton, Goddard, Tsiolkovsky, Oberth people would sit down and do a little joint study with the Maxwell, Gauss, Faraday, Weber
Yes Weber was very close to a comprehensive understanding
as was Tesla I am told.
QUOTE
the change in magnetic field. If one happens to be moving at high velocity through an unchanging magnetic field there will be no induced EMF. Conversely one could be holding still and if there is a changing magnetic field there will still be an EMF.
Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly,
Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly,
mmmh
QUOTE (->
| QUOTE |
| the change in magnetic field. If one happens to be moving at high velocity through an unchanging magnetic field there will be no induced EMF. Conversely one could be holding still and if there is a changing magnetic field there will still be an EMF. Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly, |
mmmh
(I'd bet you're confusing Lenz's law with the Lorentz force).
no
QUOTE (Zarkov+Mar 7 2008, 03:55 AM)
yes it has all to do with Lenz's Law
Demonstrated well in Mercury's precessional orbit.
The electrical charge of the planet would have to be far greater than could be possible, especially for being immersed in a plasma wind as it is (if it had a notable charge, it would be quickly neutralized by oppositely-charged plasma particles being attracted to it). Also, even if this were proved true, it would require a profound modification of GR. So it seems very unlikely.
Demonstrated well in Mercury's precessional orbit.
The electrical charge of the planet would have to be far greater than could be possible, especially for being immersed in a plasma wind as it is (if it had a notable charge, it would be quickly neutralized by oppositely-charged plasma particles being attracted to it). Also, even if this were proved true, it would require a profound modification of GR. So it seems very unlikely.
QUOTE (barakn+Mar 7 2008, 06:54 AM)
What does high velocity have to do with anything? What's important for Lenz's law is the change in magnetic field. If one happens to be moving at high velocity through an unchanging magnetic field there will be no induced EMF. Conversely one could be holding still and if there is a changing magnetic field there will still be an EMF. It's better to leave velocity out of this discussion (I'd bet you're confusing Lenz's law with the Lorentz force).
Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly, as you can see here:
http://www.swpc.noaa.gov/ace/MAG_SWEPAM_2h.html
Lenz's law may imply a force on the spacecraft but the direction of this force is constantly changing and thus over time will average out to zero. The Sun's magnetic field is not a likely source.
Thank You for considering the possibility of electromagnetic induction as a force generator in both heliocentric and geocentric orbiting bodies.
The induced voltage will be function of the velocity at which the inductor (spacecraft or subsystem components) is cutting the solar magnetic field lines. It is the velocity that provides the Rate of Change component in this specific induction process. So velocity, relative to the field, is a primary component of the induction process.
In an induction process, is the magnetic field produced as a result of the current flowing in the inductor, of opposite or same polarity as the excitation field?
If the excitation field is also modulated, does this increase the rate of induction?
If the polarity of the excitation field is reversed does this change the relative relationship of polarity between the inductor and excitation field? How does this affect the assumption that the induced sum force would be 0? Even if the time frames being considered included a polarity reversal of the excitation field which they certainly do not.
Outside the magnetic influence of strong planet field sources (Earth, Jupiter, Saturn, ect) the solar field would be the primary source of excitation field out to the heliopause where the galactic field would begin to predominate.
Unrelated to induction as a source of accelerating force:
I have come to the conclusion that the experts, instead of doing their own fundamental study, use software algorithms, often written decades ago, as full consideration of the variables in orbital elements. As an outsider I would be cautious whether the error values in the constants used in those algorithms would have the required accuracy to compute to a degree that such small anomalies can be confidently determined. What I am saying is this. There may be no other force, only software accuracy errors.
Unrelated to the accuracy of software constants used in orbital determination:
Is there such a thing as "empty space?" Would the space craft still have a "Ballistic Coefficient" even in this less than "empty space"? Could the dynamic drag of the space craft be totally ignored when considering both the high speed and time frames considered?
Gavilan
Also consider that the direction and strength of the Sun's magnetic field is changing a lot and rather randomly, as you can see here:
http://www.swpc.noaa.gov/ace/MAG_SWEPAM_2h.html
Lenz's law may imply a force on the spacecraft but the direction of this force is constantly changing and thus over time will average out to zero. The Sun's magnetic field is not a likely source.
Thank You for considering the possibility of electromagnetic induction as a force generator in both heliocentric and geocentric orbiting bodies.
The induced voltage will be function of the velocity at which the inductor (spacecraft or subsystem components) is cutting the solar magnetic field lines. It is the velocity that provides the Rate of Change component in this specific induction process. So velocity, relative to the field, is a primary component of the induction process.
In an induction process, is the magnetic field produced as a result of the current flowing in the inductor, of opposite or same polarity as the excitation field?
If the excitation field is also modulated, does this increase the rate of induction?
If the polarity of the excitation field is reversed does this change the relative relationship of polarity between the inductor and excitation field? How does this affect the assumption that the induced sum force would be 0? Even if the time frames being considered included a polarity reversal of the excitation field which they certainly do not.
Outside the magnetic influence of strong planet field sources (Earth, Jupiter, Saturn, ect) the solar field would be the primary source of excitation field out to the heliopause where the galactic field would begin to predominate.
Unrelated to induction as a source of accelerating force:
I have come to the conclusion that the experts, instead of doing their own fundamental study, use software algorithms, often written decades ago, as full consideration of the variables in orbital elements. As an outsider I would be cautious whether the error values in the constants used in those algorithms would have the required accuracy to compute to a degree that such small anomalies can be confidently determined. What I am saying is this. There may be no other force, only software accuracy errors.
Unrelated to the accuracy of software constants used in orbital determination:
Is there such a thing as "empty space?" Would the space craft still have a "Ballistic Coefficient" even in this less than "empty space"? Could the dynamic drag of the space craft be totally ignored when considering both the high speed and time frames considered?
Gavilan
opinion:
Mond is a waste of time - it can't predict gravitatiobal lensing of starlight - that's why they developed TeVeS from mond.
Facts:
1)it's a sunward acceleration - the probes aren't speeding up, they're slowing down.
2)it shows diurnal and seasonal variations.
3)they don't know yet which direction the acceleration is - whether it's genuinely sunward, or earthward, or in som other direction towars the middle.
4) they're still processimg the data for the pioneer anomaly - there's some uncertainty as to whether it started before or after the jovian flyby.
5) The paper the article is undoubtedly referring to (pretty sure I have it on my laptop hardrive) specifically states that it could be as simple as an inaccuracy in the way we computed their orbital trajectories at flyby - we knew what the incoming and outgoing trajectories should have been, the actual flyby trajectories themselves were something of an approximation - a smuch art as science (at that time). It involved matching up bezier curves.
6) The same article says that the anomaly is easy to spot for the pioneer probes because of the type of stabilization they used, but many of the probes use some other kind of stabilization that mask the effects.
Right rant done (mostly).
Here's some more facts for those that are actually interested in learning about the anomaly:
Here's the webpage for the INternational Space Science Institute collaboration that's investigating the pioneer anomaly: http://www.issibern.ch/teams/Pioneer/
Here's the webpage for the Planetary Society investigation into the pioneer anomaly: http://www.planetary.org/programs/projects...e_20070328.html
And finally, here's an Arxiv article, presented at the November '07 BIS symposium that suggests that the pioneer anomaly, and other similar observed anomalies could be due to the effects of Unruh radiation http://arxiv.org/abs/0712.3022
Mond is a waste of time - it can't predict gravitatiobal lensing of starlight - that's why they developed TeVeS from mond.
Facts:
1)it's a sunward acceleration - the probes aren't speeding up, they're slowing down.
2)it shows diurnal and seasonal variations.
3)they don't know yet which direction the acceleration is - whether it's genuinely sunward, or earthward, or in som other direction towars the middle.
4) they're still processimg the data for the pioneer anomaly - there's some uncertainty as to whether it started before or after the jovian flyby.
5) The paper the article is undoubtedly referring to (pretty sure I have it on my laptop hardrive) specifically states that it could be as simple as an inaccuracy in the way we computed their orbital trajectories at flyby - we knew what the incoming and outgoing trajectories should have been, the actual flyby trajectories themselves were something of an approximation - a smuch art as science (at that time). It involved matching up bezier curves.
6) The same article says that the anomaly is easy to spot for the pioneer probes because of the type of stabilization they used, but many of the probes use some other kind of stabilization that mask the effects.
Right rant done (mostly).
Here's some more facts for those that are actually interested in learning about the anomaly:
Here's the webpage for the INternational Space Science Institute collaboration that's investigating the pioneer anomaly: http://www.issibern.ch/teams/Pioneer/
Here's the webpage for the Planetary Society investigation into the pioneer anomaly: http://www.planetary.org/programs/projects...e_20070328.html
And finally, here's an Arxiv article, presented at the November '07 BIS symposium that suggests that the pioneer anomaly, and other similar observed anomalies could be due to the effects of Unruh radiation http://arxiv.org/abs/0712.3022
QUOTE (Gavilan+Mar 7 2008, 02:52 PM)
The induced voltage will be function of the velocity at which the inductor (spacecraft or subsystem components) is cutting the solar magnetic field lines. It is the velocity that provides the Rate of Change component in this specific induction process. So velocity, relative to the field, is a primary component of the induction process.
As I suspected, you are confusing Lenz with Lorentz. Take a good look at Lenz's law and see if the word "velocity" appears anywhere in it.
As I suspected, you are confusing Lenz with Lorentz. Take a good look at Lenz's law and see if the word "velocity" appears anywhere in it.
The ISSI objectives and asserts in 2008 are much worse than what was already published by Anderson et al in 2002.
Anderson already had looked through the data. They could definitely rule out the effects of nuclear fuel as well as thermal radiation.
Anderson already had looked through the data. They could definitely rule out the effects of nuclear fuel as well as thermal radiation.
I agree electromagnetic forces are extremely small despite the high speed, because they depend on flux variations which are very slow.
And anyway, you may trust the guys at Anderson's team to have thought to such explanations. Have a look at their paper: They have thought to many possibilities.
And anyway, you may trust the guys at Anderson's team to have thought to such explanations. Have a look at their paper: They have thought to many possibilities.
QUOTE
it would require a profound modification of GR.
What makes you think GR is the end... IMO GR is based upon time, which of course does not exist.... GR IMO is a fabrication.... at least Newtonian mechanical principles are in good agreement with observed celestial parameters.
GR can not even determine the strength of gravity on, say, Earth
GR requires gravity before it can define gravity, or even fanciful "space time"; it assumes that light speed is the limit then it incestuously proves it.... a load of hog excrement.
GR has held celestial mechanics back at least 100 years.
GR has no place at all in cosmology.
QUOTE (Enthalpy+Mar 8 2008, 03:30 PM)
The ISSI objectives and asserts in 2008 are much worse than what was already published by Anderson et al in 2002.
Anderson already had looked through the data. They could definitely rule out the effects of nuclear fuel as well as thermal radiation.
no they aren't, in fact on the website not only do thet link to the same paper you did, but a perusal reveals that although Anderson might not have attended the meetings, one of his co-authors - Turyshev attended all 3.
Oh yeah, did I also mention that Anderson, Turyshev, and Nieto - three of the papers authors, are on the ISSI proposal team?
Moreover, if you look at the agenda for the first meeting, you can see that the thermal issues they were looking into and/or modelling were related to a test probe to explore the issue further.
Anderson already had looked through the data. They could definitely rule out the effects of nuclear fuel as well as thermal radiation.
no they aren't, in fact on the website not only do thet link to the same paper you did, but a perusal reveals that although Anderson might not have attended the meetings, one of his co-authors - Turyshev attended all 3.
Oh yeah, did I also mention that Anderson, Turyshev, and Nieto - three of the papers authors, are on the ISSI proposal team?
Moreover, if you look at the agenda for the first meeting, you can see that the thermal issues they were looking into and/or modelling were related to a test probe to explore the issue further.
Quote snippet from initial link:
"This near-perfect symmetry about the equator seemed to result in a very small velocity change, in contrast to the five other flybys,"
What come to mind is craft a made from metal. Flying though the Earths electromagnetic field may induce eddy currents in the craft and the earth spinning drags the craft. Like a spinning magnet induces eddy currents in a copper cup in an old-fashioned mechanical car speed indicator.
"This near-perfect symmetry about the equator seemed to result in a very small velocity change, in contrast to the five other flybys,"
What come to mind is craft a made from metal. Flying though the Earths electromagnetic field may induce eddy currents in the craft and the earth spinning drags the craft. Like a spinning magnet induces eddy currents in a copper cup in an old-fashioned mechanical car speed indicator.
QUOTE (BigDumbWeirdo+Mar 7 2008, 02:25 AM)
Oh well, so much for space dust.
Should I follow the example set so often on this forum and insist that I was right, regardless of any and all evidence to the contrary?
Or should I simply accept that I was wrong and move on...
Stick to your guns, you $%(#%(@8. You have it.
SPACE dust, see? SPACE dust.
Empty space as a fragmentable entity.
Stick to your guns, man!
Should I follow the example set so often on this forum and insist that I was right, regardless of any and all evidence to the contrary?
Or should I simply accept that I was wrong and move on...
Stick to your guns, you $%(#%(@8. You have it.
SPACE dust, see? SPACE dust.
Empty space as a fragmentable entity.
Stick to your guns, man!
QUOTE (xtrmn8r+Mar 3 2008, 01:43 AM)
I've been away for awhile, someone may have brought this up already. Anyone got any ideas about this? Could this be the same anomaly that puzzles big bang theorists?
http://www.msnbc.msn.com/id/23410705/
Thanks for bringing up this article....I had been perviewing it elsewhere.
I have to agree somewhat with Gavilan.
It is possible there could be charge build up on the satellite surface ( possibly from cosmic rays , etc.)
Thus in passing through the EARTH'S magnetic field there would be a Lorentz force according to the usual formula.
F = qE + qv X B
Therefore it is definitely velocity dependent. HOW.....ever, the cross product ensures that the force would be orthogonal to both the velocity and the B field; and thus adds no momentum to the satellite, only a change in direction.
I wonder if anyone knows if the author of the paper has considered this.? Probably not unless there is reason to suspect charge build up on the spacecraft.
JW
http://www.msnbc.msn.com/id/23410705/
Thanks for bringing up this article....I had been perviewing it elsewhere.
I have to agree somewhat with Gavilan.
It is possible there could be charge build up on the satellite surface ( possibly from cosmic rays , etc.)
Thus in passing through the EARTH'S magnetic field there would be a Lorentz force according to the usual formula.
F = qE + qv X B
Therefore it is definitely velocity dependent. HOW.....ever, the cross product ensures that the force would be orthogonal to both the velocity and the B field; and thus adds no momentum to the satellite, only a change in direction.
I wonder if anyone knows if the author of the paper has considered this.? Probably not unless there is reason to suspect charge build up on the spacecraft.
JW
QUOTE
This near-perfect symmetry about the equator seemed to result in a very small velocity change, in contrast to the five other flybys,
yes, this says it all
The L1 and L2 points of Earth with the Sun, are almost the same value... ESGT
so around Earth and the other planets are similar, a circular inertial orbit is possible..... and as such there is no precessional resultant.
The equatorial inertial circle orbit clearly defines a preferred spin rotation
and here is the other clue
QUOTE (->
| QUOTE |
| This near-perfect symmetry about the equator seemed to result in a very small velocity change, in contrast to the five other flybys, |
yes, this says it all
The L1 and L2 points of Earth with the Sun, are almost the same value... ESGT
so around Earth and the other planets are similar, a circular inertial orbit is possible..... and as such there is no precessional resultant.
The equatorial inertial circle orbit clearly defines a preferred spin rotation
and here is the other clue
have discovered that five spacecraft each raced either a tiny bit faster or slower than expected when they flew past Earth en route to other parts of the solar system.
'Space' can be characterised as bubbles of spinning fields within and without other bubbles. Traveling between the bubbles along the slipstreams is the most efficient.
Passing through and along a non inertial orbit for the Earth will result in inward and outward forces generated by Earth field spin, that would then appear to earth observers as abnormal Newtonian inertia velocity shifts.
It all depends on what you think causes 'gravity' the resultant.
QUOTE
"Another thing in common between the Pioneer and these flybys is what you would call an unbound orbit around a central body," Anderson said. "For instance, the Pioneers are flying out of the solar system — they're not bound to their central body, the sun. For the other flybys, the Earth is the central body. These kinds of orbits just don't occur very often in nature — it could be when you get into an unbound orbit around a central body, something goes on that's not in our standard models."
Spin is central body oriented... however the Earth's limits are L1 and L2.
This guys are starting to talk Electro-spin gravity theory
Zarkov=certifiable loon
QUOTE (barakn+Mar 8 2008, 01:08 AM)
As I suspected, you are confusing Lenz with Lorentz. Take a good look at Lenz's law and see if the word "velocity" appears anywhere in it.
From Handbook of Chemistry and Physics - 61st Edition.
Lenz's law - When an electromotive force is induced in a conductor by any change in the relation between the conductor and the magnetic field, the direction of the electromotive force is such as to produce a current whose magnetic field will oppose the change.
From Dictionary of Science S I - fourth edition:
Lenz's Law- When a circuit and magnetic field move relatively to each other, the electric current induced in the circuit will have a magnetic field opposing the motion.
From Physics for Scientists and Engineers - page 588 in discussion of Lenz's Law- "---the induced current is in the direction that produces a magnetic force that opposes the external force."
From College Physics- 4th edition - Miller- "Lenz's Law; An induced emf tends to set up a current whose action opposes the change that caused it."
End quotes.
The word "velocity" does not need to appear in the definitions. It is a primary component of any induction process where the excitation field remains near constant. The induced voltage varies directly as the velocity and excitation field strength. Again, in this induction process the "rate of change" components are solar field strength and space craft velocity relative to that field.
Gavilan
From Handbook of Chemistry and Physics - 61st Edition.
Lenz's law - When an electromotive force is induced in a conductor by any change in the relation between the conductor and the magnetic field, the direction of the electromotive force is such as to produce a current whose magnetic field will oppose the change.
From Dictionary of Science S I - fourth edition:
Lenz's Law- When a circuit and magnetic field move relatively to each other, the electric current induced in the circuit will have a magnetic field opposing the motion.
From Physics for Scientists and Engineers - page 588 in discussion of Lenz's Law- "---the induced current is in the direction that produces a magnetic force that opposes the external force."
From College Physics- 4th edition - Miller- "Lenz's Law; An induced emf tends to set up a current whose action opposes the change that caused it."
End quotes.
The word "velocity" does not need to appear in the definitions. It is a primary component of any induction process where the excitation field remains near constant. The induced voltage varies directly as the velocity and excitation field strength. Again, in this induction process the "rate of change" components are solar field strength and space craft velocity relative to that field.
Gavilan
Some reasons that speak against electromagnetic forces:
- The extra "drag" experienced by both Pioneers is roughly constant over distance. The Sun's magnetic field, however, declines quickly with the distance. The particle density of interplanetary medium also decreases with the square of distance. And this distance has already varied a lot over the time the "drag" was observed.
- Science is nothing without figures. Take about 6nT at 1 AU, you may have 6pT to less than 600pT at 10AU, this higher figure inducing 100µV in 10m arms at 20km/s. For speed and constant field to make a force, the current would then have to close the loop through immobile medium - that is, through a quite void vacuum: About 200 electrons /m3 at 10AU.
So an electron of the interplanetary medium experiencing 100µV/10m during 10m/(20km/s) would receive 800m/s speed through the induced electromagnetic force, much less than the 20km/s spacecraft speed, hence this force is 25^2 times lower than the "aerodynamic" drag itself, which is already too small. The comparison would be even clearer with the protons and alphas.
- Pulsations and rotation of this field would push spacecrafts away from the Sun instead of attracting them.
Not necessarily the best source:
http://pluto.space.swri.edu/image/glossary/IMF.html
but nice drawings.
- The extra "drag" experienced by both Pioneers is roughly constant over distance. The Sun's magnetic field, however, declines quickly with the distance. The particle density of interplanetary medium also decreases with the square of distance. And this distance has already varied a lot over the time the "drag" was observed.
- Science is nothing without figures. Take about 6nT at 1 AU, you may have 6pT to less than 600pT at 10AU, this higher figure inducing 100µV in 10m arms at 20km/s. For speed and constant field to make a force, the current would then have to close the loop through immobile medium - that is, through a quite void vacuum: About 200 electrons /m3 at 10AU.
So an electron of the interplanetary medium experiencing 100µV/10m during 10m/(20km/s) would receive 800m/s speed through the induced electromagnetic force, much less than the 20km/s spacecraft speed, hence this force is 25^2 times lower than the "aerodynamic" drag itself, which is already too small. The comparison would be even clearer with the protons and alphas.
- Pulsations and rotation of this field would push spacecrafts away from the Sun instead of attracting them.
Not necessarily the best source:
http://pluto.space.swri.edu/image/glossary/IMF.html
but nice drawings.
If somebody launches a spacecraft (or many ones) to observe the Pioneer anomaly, it could be very nice to combine it with pulsar navigation.
Let me remind this nice idea: Spacecrafts would carry radio receivers to measure the relative times of arrival of the pulses emitted by several pulsars. When receiving its pulse sooner, the spacecraft knows it is closer to a particular pulsar. By observing many pulsars, the spacecraft determines its position in 3D like a GPS receiver does, without any help from Earth stations.
First, Pioneer anomaly spacecrafts would be nice platforms to test the pulsar navigation, since such spacecrafts would be designed to have a very predictable and well-measured trajectory.
Then, we would get measurements of the tangential speed and not just the radial speed - though the pulsar navigation might be too imprecise to test the Pioneer anomaly.
And best, if we can somehow achieve the necessary accuracy, it would give us a speed measured to a reference outside the Solar system, and not just relative to the Earth, which may prove decisive if we're to look for a new physical effect, or even new theories.
However, with radio fluxes in the order of 1 Jansky, we may have to give up the unstabilized spacecraft: It would need high-gain antennas (and heavy signal processing), more probably dish antennas than synthetic aperture.
Let me remind this nice idea: Spacecrafts would carry radio receivers to measure the relative times of arrival of the pulses emitted by several pulsars. When receiving its pulse sooner, the spacecraft knows it is closer to a particular pulsar. By observing many pulsars, the spacecraft determines its position in 3D like a GPS receiver does, without any help from Earth stations.
First, Pioneer anomaly spacecrafts would be nice platforms to test the pulsar navigation, since such spacecrafts would be designed to have a very predictable and well-measured trajectory.
Then, we would get measurements of the tangential speed and not just the radial speed - though the pulsar navigation might be too imprecise to test the Pioneer anomaly.
And best, if we can somehow achieve the necessary accuracy, it would give us a speed measured to a reference outside the Solar system, and not just relative to the Earth, which may prove decisive if we're to look for a new physical effect, or even new theories.
However, with radio fluxes in the order of 1 Jansky, we may have to give up the unstabilized spacecraft: It would need high-gain antennas (and heavy signal processing), more probably dish antennas than synthetic aperture.
QUOTE (Gavilan+Mar 8 2008, 08:00 AM)
From Handbook of Chemistry and Physics - 61st Edition.
Lenz's law - When an electromotive force is induced in a conductor by any change in the relation between the conductor and the magnetic field, the direction of the electromotive force is such as to produce a current whose magnetic field will oppose the change.
From Dictionary of Science S I - fourth edition:
Lenz's Law- When a circuit and magnetic field move relatively to each other, the electric current induced in the circuit will have a magnetic field opposing the motion.
From Physics for Scientists and Engineers - page 588 in discussion of Lenz's Law- "---the induced current is in the direction that produces a magnetic force that opposes the external force."
From College Physics- 4th edition - Miller- "Lenz's Law; An induced emf tends to set up a current whose action opposes the change that caused it."
End quotes.
The word "velocity" does not need to appear in the definitions. It is a primary component of any induction process where the excitation field remains near constant. The induced voltage varies directly as the velocity and excitation field strength. Again, in this induction process the "rate of change" components are solar field strength and space craft velocity relative to that field.
Gavilan
The important concept in Lenz's law is the magnetic flux through an area bounded by a conductor. In order for there to be an induced EMF, there must be a change in the magnetic flux. In a very large magnetic field where the strength and direction of the field is pretty much identical at one point as at another point a 1000 meters away, there won't be a change in the magnetic flux as a conducting loop flies from that one point to the other (as long as it's not rotating) no matter what its velocity is.
Conversely one could have a conducting loop a static distance away from an electromagnet (oriented so that the loop isn't parallel to the field). Turn off the current in the electromagnet and there will be a change in the magnetic flux through the loop as the magnetic field decays, inducing an EMF in the loop. Notice that the loop's velocity is zero with respect to the source of the field.
The only conclusion from these two examples is that velocity is not integral to Lenz's law. The Dictionary of Science and Physics for Scientists and Engineers definitions are wrong or incomplete. I don't have a problem with the Handbook Of Chemistry and Physics or the College Physics definitions.
Having said that, Lenz's law will be in play for a spacecraft. Care to address my point that the constantly changing Solar magnetic field causes randomly oriented forces of random magnitudes on the spacecraft? How would that result in a change in velocity that's consistently towards the Sun?
Lenz's law - When an electromotive force is induced in a conductor by any change in the relation between the conductor and the magnetic field, the direction of the electromotive force is such as to produce a current whose magnetic field will oppose the change.
From Dictionary of Science S I - fourth edition:
Lenz's Law- When a circuit and magnetic field move relatively to each other, the electric current induced in the circuit will have a magnetic field opposing the motion.
From Physics for Scientists and Engineers - page 588 in discussion of Lenz's Law- "---the induced current is in the direction that produces a magnetic force that opposes the external force."
From College Physics- 4th edition - Miller- "Lenz's Law; An induced emf tends to set up a current whose action opposes the change that caused it."
End quotes.
The word "velocity" does not need to appear in the definitions. It is a primary component of any induction process where the excitation field remains near constant. The induced voltage varies directly as the velocity and excitation field strength. Again, in this induction process the "rate of change" components are solar field strength and space craft velocity relative to that field.
Gavilan
The important concept in Lenz's law is the magnetic flux through an area bounded by a conductor. In order for there to be an induced EMF, there must be a change in the magnetic flux. In a very large magnetic field where the strength and direction of the field is pretty much identical at one point as at another point a 1000 meters away, there won't be a change in the magnetic flux as a conducting loop flies from that one point to the other (as long as it's not rotating) no matter what its velocity is.
Conversely one could have a conducting loop a static distance away from an electromagnet (oriented so that the loop isn't parallel to the field). Turn off the current in the electromagnet and there will be a change in the magnetic flux through the loop as the magnetic field decays, inducing an EMF in the loop. Notice that the loop's velocity is zero with respect to the source of the field.
The only conclusion from these two examples is that velocity is not integral to Lenz's law. The Dictionary of Science and Physics for Scientists and Engineers definitions are wrong or incomplete. I don't have a problem with the Handbook Of Chemistry and Physics or the College Physics definitions.
Having said that, Lenz's law will be in play for a spacecraft. Care to address my point that the constantly changing Solar magnetic field causes randomly oriented forces of random magnitudes on the spacecraft? How would that result in a change in velocity that's consistently towards the Sun?
all the above definitions of Lenz's law are deficient, though the gist is correct.
Not one of them mention acceleration.
The concept of Newtonian inertia is incorrect.
Not one of them mention acceleration.
The concept of Newtonian inertia is incorrect.
QUOTE (Zarkov+)
The concept of Newtonian inertia is incorrect.
You really are a loon
You really are a loon
Spacecrafts designed to measure the Pioneer anomaly:
The above proposal with many crafts relaying their pulses allows to see if the force acts differently on different spacecrafts, but isn't very precise (well, unless you have very precise clocks onboard) for measuring the absolute effect. And in order to check a deviation from the usual gravity law for instance, which would act identically on all crafts, we need an absolute measure.
So we need a bidirectional transmission, Earth - spacecrafts - Earth, to measure precisely the speed without relying on extremely precise clocks.
Surprisingly enough, this can still be achieved without an attitude control, hence with omnidirectional antennas on the spacecrafts, despite these antennas have no gain. How is this possible at such a distance? Because the transmitting antennas at Earth are that powerful...
The Deep Space Network has transmitters of
400kW feeding antennas of D = 60m
Billions of blistering barnacles in a thundering typhoon!
At a distance of 20 hours-light (!), the isotropic antennas on the spacecrafts would still receive 53e-21W, which is 100K in a 40Hz band! This means that any stupid FFT would easily recover the exact carrier frequency within the 300kHz band due to Doppler effect at 3GHz and 30km/s.
The rest is details. I would measure the drift of the onboard clock instead of compensating it, and lock the transmitted frequency by a DDS for instance. And to measure the distance, I would transmit a pure frequency followed by a ping instead of combining them, as this is simpler and power is plentiful. However, maintaining phase coherence from one uplink session to the next one is probably too difficult for the clock, so the desired speed accuracy must be brought by the duration of one session. Anyway, 1 min transmission duration with a bad SNR at 3GHz already gives 0.1mm/s accuracy on the speed.
So the spacecrafts can still avoid any kind of attitude control, making them very simple, and allowing a predictable and observable trajectory.
The above proposal with many crafts relaying their pulses allows to see if the force acts differently on different spacecrafts, but isn't very precise (well, unless you have very precise clocks onboard) for measuring the absolute effect. And in order to check a deviation from the usual gravity law for instance, which would act identically on all crafts, we need an absolute measure.
So we need a bidirectional transmission, Earth - spacecrafts - Earth, to measure precisely the speed without relying on extremely precise clocks.
Surprisingly enough, this can still be achieved without an attitude control, hence with omnidirectional antennas on the spacecrafts, despite these antennas have no gain. How is this possible at such a distance? Because the transmitting antennas at Earth are that powerful...
The Deep Space Network has transmitters of
400kW feeding antennas of D = 60m
Billions of blistering barnacles in a thundering typhoon!
At a distance of 20 hours-light (!), the isotropic antennas on the spacecrafts would still receive 53e-21W, which is 100K in a 40Hz band! This means that any stupid FFT would easily recover the exact carrier frequency within the 300kHz band due to Doppler effect at 3GHz and 30km/s.
The rest is details. I would measure the drift of the onboard clock instead of compensating it, and lock the transmitted frequency by a DDS for instance. And to measure the distance, I would transmit a pure frequency followed by a ping instead of combining them, as this is simpler and power is plentiful. However, maintaining phase coherence from one uplink session to the next one is probably too difficult for the clock, so the desired speed accuracy must be brought by the duration of one session. Anyway, 1 min transmission duration with a bad SNR at 3GHz already gives 0.1mm/s accuracy on the speed.
So the spacecrafts can still avoid any kind of attitude control, making them very simple, and allowing a predictable and observable trajectory.
To transmit (and receive) radiowaves through the multilayer thermal insulator, I suggested to slit the metal coating from place to place.
There is another possibility, maybe simpler and more efficient.
Don't metalize the plastic film, and put 3000 plies instead of 100. Still acceptably thin, and weight isn't that critical on this project.
A further refinement could be to make the vacuum a quarter wavelength thick between the plies, or 2.5µm at 300K, in an attempt to let the refraction index reflect more IR light. A coating of Ge or TiO2, with their high index, could help further.
Anyway, I wonder if a dense felt of really thin fibers wouldn't be just as good as this multilayer junk. Soviet spacecrafts used such down jackets, but I don't have figures of their efficiency.
Wouldn't that be cute: A spacecraft in a fur coat?
There is another possibility, maybe simpler and more efficient.
Don't metalize the plastic film, and put 3000 plies instead of 100. Still acceptably thin, and weight isn't that critical on this project.
A further refinement could be to make the vacuum a quarter wavelength thick between the plies, or 2.5µm at 300K, in an attempt to let the refraction index reflect more IR light. A coating of Ge or TiO2, with their high index, could help further.
Anyway, I wonder if a dense felt of really thin fibers wouldn't be just as good as this multilayer junk. Soviet spacecrafts used such down jackets, but I don't have figures of their efficiency.
Wouldn't that be cute: A spacecraft in a fur coat?
Sub-details about the transmission:
As the mid-time part of the pure frequency burst is useless for determining the Doppler speed, a better combination is to transmit the ping for range determination (usually a PN sequence, or a chirp some time ago) at the mid-time of the session.
So the message would better be: pure frequency - range ping - pure frequency.
Once you've transmitted and received that, you also have everything you need (carrier frequency and Doppler, plus message and symbol synchronization) to transmit a few bits, something every spacecraft project leader wants to do: Battery voltage, temperature, spinning frequency, measured Doppler, signal force...
Then the message becomes: pure frequency - range ping - some bits - pure frequency.
The information throughput will be quite low because of the distance and the isotropic antennas. Doppler and range measurements can accept it, but datacomms suffer from it.
As the mid-time part of the pure frequency burst is useless for determining the Doppler speed, a better combination is to transmit the ping for range determination (usually a PN sequence, or a chirp some time ago) at the mid-time of the session.
So the message would better be: pure frequency - range ping - pure frequency.
Once you've transmitted and received that, you also have everything you need (carrier frequency and Doppler, plus message and symbol synchronization) to transmit a few bits, something every spacecraft project leader wants to do: Battery voltage, temperature, spinning frequency, measured Doppler, signal force...
Then the message becomes: pure frequency - range ping - some bits - pure frequency.
The information throughput will be quite low because of the distance and the isotropic antennas. Doppler and range measurements can accept it, but datacomms suffer from it.
Maintaining phase coherence looks better than I first thought.
Look: If we say that the clock mismatch can be as big as 1e-4 to account for the Doppler effect at 30km/s, all we need to do is uplink the ranging ping only at special times.
That is, if we ping at least once in a month, than we chose times multiples of 5 min to do it. As the spacecrafts knows that the ping belongs to one of these special times, it can decide which possible time is nearest, and this will be exact.
Then, if we have enough bandwidth for 30Mbps spreading for the ping, the correlation goes from max to zero within 33ns. Already a nice precision.
Now, remember the spacecraft receives 0dB SNR at 40Hz bandwidth (-163dBm). This means that with 0.04Hz bandwidth or (approx!) 25s ping duration, we get 40dB SNR on the correlation, and we can determine the position of the PN sequence with 0.33ns accuracy.
[Yes, convolving for 25s at 30 MHz would require some processing power, but there are tricks, for instance adding repetitive shorter sequences. And who cares such subsubsubdetails anyway?]
This is one period of the 3GHz carrier frequency. So we can achieve phase coherence, which means an incredible precision on the range measurement.
The only remaining limit is how long the onboard clock can maintain such an accuracy. In fact, this is the limiting factor, even over a few seconds or minutes. A possible workaround would be to transmit while still receiving the prolonged uplink signal; Difficult with 100W and 50e-21W!
I wouldn't go further than one wavelength despite we have SNR on the carrier, because the free-spinning spacecraft means that each antenna moves towards and away from Earth.
Look: If we say that the clock mismatch can be as big as 1e-4 to account for the Doppler effect at 30km/s, all we need to do is uplink the ranging ping only at special times.
That is, if we ping at least once in a month, than we chose times multiples of 5 min to do it. As the spacecrafts knows that the ping belongs to one of these special times, it can decide which possible time is nearest, and this will be exact.
Then, if we have enough bandwidth for 30Mbps spreading for the ping, the correlation goes from max to zero within 33ns. Already a nice precision.
Now, remember the spacecraft receives 0dB SNR at 40Hz bandwidth (-163dBm). This means that with 0.04Hz bandwidth or (approx!) 25s ping duration, we get 40dB SNR on the correlation, and we can determine the position of the PN sequence with 0.33ns accuracy.
[Yes, convolving for 25s at 30 MHz would require some processing power, but there are tricks, for instance adding repetitive shorter sequences. And who cares such subsubsubdetails anyway?]
This is one period of the 3GHz carrier frequency. So we can achieve phase coherence, which means an incredible precision on the range measurement.
The only remaining limit is how long the onboard clock can maintain such an accuracy. In fact, this is the limiting factor, even over a few seconds or minutes. A possible workaround would be to transmit while still receiving the prolonged uplink signal; Difficult with 100W and 50e-21W!
I wouldn't go further than one wavelength despite we have SNR on the carrier, because the free-spinning spacecraft means that each antenna moves towards and away from Earth.
I had hoped to accelerate the spacecrafts to 30km/s relative to Earth... This looks bad!
This was just a false memory of Ulysses. I believed its launcher had added 30km/s to the 30km/s Earth's orbital speed: mistake! Ulysses had only 15,3km/s, after firing two solid rockets beginning from low-Earth orbit.
One spacecraft departed Earth faster than Ulysses: New Horizons had 16,2km/s adding to the Earth's 29.8km/s. This would be enough to escape the Sun's attraction (42.1km/s) even if it didn't use Jupiter's slingshot help.
Even though the rocket stage combination in both cases was suboptimum, there is no reasonable way to achieve 30km/s departure speed with chemical rockets. Just to get a picture: New Horizons weighed 478kg, its launcher 540t...
Better propulsion means don't have the same degree of simplicity as the spacecrafts I describe above. Gravitation slingshot by Jupiter also needs a precise navigation by the crafts themselves, which would make them complicated again. So the only option is to accept a lower speed and wait longer.
With 16,2km/s departure speed vs Earth and without slingshot effect, the remaining speed far away from the Sun is 18,5km/s or 30min-light per year. After 10 years, the distance should be in the order of 50AU, about twice the distance of Neptune, quite good for the purpose.
If launching a group of 5 crafts weighing 15kg each, they should total 100kg with the adapter, so the rocket can be smaller and hopefully cheaper than an Atlas V 551, something like a Falcon-9 (rumoured to cost 35M$) or a Zenith.
This was just a false memory of Ulysses. I believed its launcher had added 30km/s to the 30km/s Earth's orbital speed: mistake! Ulysses had only 15,3km/s, after firing two solid rockets beginning from low-Earth orbit.
One spacecraft departed Earth faster than Ulysses: New Horizons had 16,2km/s adding to the Earth's 29.8km/s. This would be enough to escape the Sun's attraction (42.1km/s) even if it didn't use Jupiter's slingshot help.
Even though the rocket stage combination in both cases was suboptimum, there is no reasonable way to achieve 30km/s departure speed with chemical rockets. Just to get a picture: New Horizons weighed 478kg, its launcher 540t...
Better propulsion means don't have the same degree of simplicity as the spacecrafts I describe above. Gravitation slingshot by Jupiter also needs a precise navigation by the crafts themselves, which would make them complicated again. So the only option is to accept a lower speed and wait longer.
With 16,2km/s departure speed vs Earth and without slingshot effect, the remaining speed far away from the Sun is 18,5km/s or 30min-light per year. After 10 years, the distance should be in the order of 50AU, about twice the distance of Neptune, quite good for the purpose.
If launching a group of 5 crafts weighing 15kg each, they should total 100kg with the adapter, so the rocket can be smaller and hopefully cheaper than an Atlas V 551, something like a Falcon-9 (rumoured to cost 35M$) or a Zenith.
QUOTE (barakn+Mar 8 2008, 09:19 PM)
The important concept in Lenz's law is the magnetic flux through an area bounded by a conductor. In order for there to be an induced EMF, there must be a change in the magnetic flux. In a very large magnetic field where the strength and direction of the field is pretty much identical at one point as at another point a 1000 meters away, there won't be a change in the magnetic flux as a conducting loop flies from that one point to the other (as long as it's not rotating) no matter what its velocity is.
Conversely one could have a conducting loop a static distance away from an electromagnet (oriented so that the loop isn't parallel to the field). Turn off the current in the electromagnet and there will be a change in the magnetic flux through the loop as the magnetic field decays, inducing an EMF in the loop. Notice that the loop's velocity is zero with respect to the source of the field.
The only conclusion from these two examples is that velocity is not integral to Lenz's law. The Dictionary of Science and Physics for Scientists and Engineers definitions are wrong or incomplete. I don't have a problem with the Handbook Of Chemistry and Physics or the College Physics definitions.
Having said that, Lenz's law will be in play for a spacecraft. Care to address my point that the constantly changing Solar magnetic field causes randomly oriented forces of random magnitudes on the spacecraft? How would that result in a change in velocity that's consistently towards the Sun?
I will refer to the induced voltage in the Shuttle Tether experiments. Would Earths electromagnetic field be considered a "very large magnetic field?" Are you suggesting that that it is the "Rotation" of the Earth and Earth's magnetic field that caused the induced voltage in the tether? I will suggest that it was the velocity of the tether cutting the Earth's field lines that induced the several thousand volt EMF.
I understand self inductance. I have no argument regarding the collapsing field in the coil as you described.
The space craft velocity is supplying the rate component.
Induction occurs whether a magnetic field is changing and the inductor remains motionless, the inductor is moving through an magnetic field of constant strength, or a combination of both; regardless of how "very large" the magnetic field may be relative to the inductor.
The space craft is following a hyperbolic trajectory. The flight path angle relative to the solar field defines the angle in the equation for induction. I question your assumption that the rate change of solar field would be of greater significance than space craft velocity, even considering the obliqueness of the velocity vector relative to the field lines.
Conversely one could have a conducting loop a static distance away from an electromagnet (oriented so that the loop isn't parallel to the field). Turn off the current in the electromagnet and there will be a change in the magnetic flux through the loop as the magnetic field decays, inducing an EMF in the loop. Notice that the loop's velocity is zero with respect to the source of the field.
The only conclusion from these two examples is that velocity is not integral to Lenz's law. The Dictionary of Science and Physics for Scientists and Engineers definitions are wrong or incomplete. I don't have a problem with the Handbook Of Chemistry and Physics or the College Physics definitions.
Having said that, Lenz's law will be in play for a spacecraft. Care to address my point that the constantly changing Solar magnetic field causes randomly oriented forces of random magnitudes on the spacecraft? How would that result in a change in velocity that's consistently towards the Sun?
I will refer to the induced voltage in the Shuttle Tether experiments. Would Earths electromagnetic field be considered a "very large magnetic field?" Are you suggesting that that it is the "Rotation" of the Earth and Earth's magnetic field that caused the induced voltage in the tether? I will suggest that it was the velocity of the tether cutting the Earth's field lines that induced the several thousand volt EMF.
I understand self inductance. I have no argument regarding the collapsing field in the coil as you described.
The space craft velocity is supplying the rate component.
Induction occurs whether a magnetic field is changing and the inductor remains motionless, the inductor is moving through an magnetic field of constant strength, or a combination of both; regardless of how "very large" the magnetic field may be relative to the inductor.
The space craft is following a hyperbolic trajectory. The flight path angle relative to the solar field defines the angle in the equation for induction. I question your assumption that the rate change of solar field would be of greater significance than space craft velocity, even considering the obliqueness of the velocity vector relative to the field lines.
QUOTE
The space craft velocity is supplying the rate component.
only if the trajectory is not "inertial" (as in equatorial and circular)
see
QUOTE (->
| QUOTE |
| The space craft velocity is supplying the rate component. |
only if the trajectory is not "inertial" (as in equatorial and circular)
see
The space craft is following a hyperbolic trajectory
maybe with Earth but they would be in a very elliptical orbit with the Sun
thus cutting Earth's spin field and inducing a magnetic/electric reaction
With the orbit of Mercury, Lenz's law plays the role of causing the planet to swing back and out... with precession....the orbit is very very elliptical, so there are massive "repelling" forces at work.
Conclusions from ESGT
I've already given an answer with figures explaining electromagnetic forces are too small.
Anderson et al did it before, of course. If you eventually read their paper (address in this topic), you will notice they did check many more explanations - electromagnetic forces, dust, gases being the most elementary of them.
Don't imagine people haven't thought of it... It simply doesn't work. So if you believe everybody has missed something, don't just make comparisons (the Shuttle tether is exactly what I computed, with the circuit closed through the interplanetary plasma): please tell how much, why, how... As in a normal scientific discussion.
Anderson et al did it before, of course. If you eventually read their paper (address in this topic), you will notice they did check many more explanations - electromagnetic forces, dust, gases being the most elementary of them.
Don't imagine people haven't thought of it... It simply doesn't work. So if you believe everybody has missed something, don't just make comparisons (the Shuttle tether is exactly what I computed, with the circuit closed through the interplanetary plasma): please tell how much, why, how... As in a normal scientific discussion.
QUOTE
Anderson et al did it before, of course. If you eventually read their paper (address in this topic), you will notice they did check many more explanations - electromagnetic forces, dust, gases being the most elementary of them
This was for the Pioneer anomaly... that is caused by a different process... Jupiter et al (energy) speeding up the Sun's field spin at distance and outwards... rection towards the Sun
I was referring to the "passing spacecraft" anomaly.
The Tether experiment is somewhat similar in that the tether was NOT INERTIAL, even though the Shuttle was inertial..., so yes the tether charged up.
QUOTE (Gavilan+Mar 21 2008, 03:39 AM)
I will refer to the induced voltage in the Shuttle Tether experiments. Would Earths electromagnetic field be considered a "very large magnetic field?" Are you suggesting that that it is the "Rotation" of the Earth and Earth's magnetic field that caused the induced voltage in the tether? I will suggest that it was the velocity of the tether cutting the Earth's field lines that induced the several thousand volt EMF.
I understand self inductance. I have no argument regarding the collapsing field in the coil as you described.
The space craft velocity is supplying the rate component.
Induction occurs whether a magnetic field is changing and the inductor remains motionless, the inductor is moving through an magnetic field of constant strength, or a combination of both; regardless of how "very large" the magnetic field may be relative to the inductor.
The space craft is following a hyperbolic trajectory. The flight path angle relative to the solar field defines the angle in the equation for induction. I question your assumption that the rate change of solar field would be of greater significance than space craft velocity, even considering the obliqueness of the velocity vector relative to the field lines.
Gavilan,
The shuttle tether is a very interesting example. It had me vacillating on my position.
This comes from the bottom of a poorly-written wiki article on homopolar generators:
The statement about special relativity and a uniform magnetic field is essentially the same claim that I've been making. When applying the question "the velocity relative to what?" it becomes obvious that the tether is flying past a bunch of electrons trapped in the Earth's magnetic field (assuming an equatorial orbit so the electrons do have a degree of freedom but which is perpendicular to the tether's velocity). It is these free electrons which not only are necessary to form the return current but which also experience a Lorentz force that pushes them to one end of the tether to initiate the current in the tether in the first place.
So my position as it now stands is that there could be a small amount of force due to eddy currents and Faraday's law within conducting pieces as the satellite moves through varying magnetic fields (most B fields in space are big though so the variation doesn't occur quickly) or due to Lorentz force as it flies through uniform B fields and encounters free electrons trapped therein forming circuits which exist partially within the conductive areas and partially in free space. However, since the satellite is not likely to have a long extended shape perpendicular to the B field, I expect these currents and thus the force to also be weak. I think we may be closer to agreement, if only a tad.
And no, the homopolar generator did not come out of left field, it was mentioned on the wiki page on electrodynamic tethers. The quote above does contain at least one error, claiming Faraday's law is a cross product involving the magnetic flux vector when it should just be the magnetic field vector.
I understand self inductance. I have no argument regarding the collapsing field in the coil as you described.
The space craft velocity is supplying the rate component.
Induction occurs whether a magnetic field is changing and the inductor remains motionless, the inductor is moving through an magnetic field of constant strength, or a combination of both; regardless of how "very large" the magnetic field may be relative to the inductor.
The space craft is following a hyperbolic trajectory. The flight path angle relative to the solar field defines the angle in the equation for induction. I question your assumption that the rate change of solar field would be of greater significance than space craft velocity, even considering the obliqueness of the velocity vector relative to the field lines.
Gavilan,
The shuttle tether is a very interesting example. It had me vacillating on my position.
This comes from the bottom of a poorly-written wiki article on homopolar generators:
QUOTE
Like all dynamos, the Faraday disc converts kinetic energy to electrical energy. However, unlike all other dynamos, this machine cannot be analysed using Faraday's own law of electromagnetic induction. This law (in its modern form) states that an electric current is induced in a closed electrical circuit when the magnetic flux enclosed by the circuit changes (in either magnitude or direction). However, the circuit in the Faraday disc is parallel to the magnetic field vector and therefore encloses no magnetic flux. Therefore, Faraday's law does not apply to this machine.
Instead, the Lorentz force law is used to explain the machine's behaviour. This law, discovered thirty years after Faraday's death, states that the force on an electron is proportional to the cross product of its velocity and the magnetic flux vector. In geometrical terms, this means that the force is at right-angles to both the velocity (azimuthal) and the magnetic flux (axial), which is therefore in a radial direction. The radial movement of the electron then creates an electric current between the centre of the disc and its rim.
There is a subtle difficulty in this explanation, which often leads to a misunderstanding of how the machine works. The key word in the preceding paragraph is velocity, which prompts the question, "velocity relative to what?". If the velocity relative to the magnet is assumed as the cause of the Lorentz force, then the explanation contradicts special relativity, which states that it is impossible to tell whether a uniform magnetic field is moving or stationary. This assumption would also imply that rotating the magnet and not the disc would cause a current to flow, which is not what experimenters have found.
The correct interpretation of the velocity of the electron is that it is relative to the static parts of the machine, which are the sliding contacts and the circuit to which they are connected. In the language of special relativity, these objects act as the 'observer'. It is the velocity of the electron relative to these components that causes it to experience the Lorentz force.
Instead, the Lorentz force law is used to explain the machine's behaviour. This law, discovered thirty years after Faraday's death, states that the force on an electron is proportional to the cross product of its velocity and the magnetic flux vector. In geometrical terms, this means that the force is at right-angles to both the velocity (azimuthal) and the magnetic flux (axial), which is therefore in a radial direction. The radial movement of the electron then creates an electric current between the centre of the disc and its rim.
There is a subtle difficulty in this explanation, which often leads to a misunderstanding of how the machine works. The key word in the preceding paragraph is velocity, which prompts the question, "velocity relative to what?". If the velocity relative to the magnet is assumed as the cause of the Lorentz force, then the explanation contradicts special relativity, which states that it is impossible to tell whether a uniform magnetic field is moving or stationary. This assumption would also imply that rotating the magnet and not the disc would cause a current to flow, which is not what experimenters have found.
The correct interpretation of the velocity of the electron is that it is relative to the static parts of the machine, which are the sliding contacts and the circuit to which they are connected. In the language of special relativity, these objects act as the 'observer'. It is the velocity of the electron relative to these components that causes it to experience the Lorentz force.
The statement about special relativity and a uniform magnetic field is essentially the same claim that I've been making. When applying the question "the velocity relative to what?" it becomes obvious that the tether is flying past a bunch of electrons trapped in the Earth's magnetic field (assuming an equatorial orbit so the electrons do have a degree of freedom but which is perpendicular to the tether's velocity). It is these free electrons which not only are necessary to form the return current but which also experience a Lorentz force that pushes them to one end of the tether to initiate the current in the tether in the first place.
So my position as it now stands is that there could be a small amount of force due to eddy currents and Faraday's law within conducting pieces as the satellite moves through varying magnetic fields (most B fields in space are big though so the variation doesn't occur quickly) or due to Lorentz force as it flies through uniform B fields and encounters free electrons trapped therein forming circuits which exist partially within the conductive areas and partially in free space. However, since the satellite is not likely to have a long extended shape perpendicular to the B field, I expect these currents and thus the force to also be weak. I think we may be closer to agreement, if only a tad.
And no, the homopolar generator did not come out of left field, it was mentioned on the wiki page on electrodynamic tethers. The quote above does contain at least one error, claiming Faraday's law is a cross product involving the magnetic flux vector when it should just be the magnetic field vector.
Where is the Bary-center of the Solar System?
How is the position of the Bary-center affected by Jupiter's orbit?
As Pioneer follows it's heliocentric hyperbolic trajectory, how does it's position change relative to solar system Bary-center?
As Bary-center revolves about Sun, on the approximate Jupiter orbital plane, how does this change the R vector force acting on Pioneer?
How does the flight path angle (relative to Bary-center) change as the position of Bary-center changes?
Gavilan
How is the position of the Bary-center affected by Jupiter's orbit?
As Pioneer follows it's heliocentric hyperbolic trajectory, how does it's position change relative to solar system Bary-center?
As Bary-center revolves about Sun, on the approximate Jupiter orbital plane, how does this change the R vector force acting on Pioneer?
How does the flight path angle (relative to Bary-center) change as the position of Bary-center changes?
Gavilan
All this is already accounted for in Anderson et al's paper.
What about reading it before?
What about reading it before?
QUOTE (Enthalpy+Mar 28 2008, 01:47 AM)
All this is already accounted for in Anderson et al's paper.
What about reading it before?
Birkeland currents!
Plasma ruLeZ!
What about reading it before?
Birkeland currents!
Plasma ruLeZ!
Enthalpy has stated on numerous occasions that:
"All this is already accounted for in Anderson et al's paper.
What about reading it before? "
Please be patient with me, could you tell me where to look in the paper? I was unable to identify either of these issues as being addressed. I am not saying that these issues were not addressed, just that I missed it in my perusal.
I am most interested in this specific paper addressing the following two issues:
1. Electro-dynamic braking resulting from the interaction of the conductive materials aboard the spacecraft and solar magnetic field.
2. The variability of the flight path angles relative to Solar System Bary-center.
Your patience and direction is appreciated.
Gavilan
"All this is already accounted for in Anderson et al's paper.
What about reading it before? "
Please be patient with me, could you tell me where to look in the paper? I was unable to identify either of these issues as being addressed. I am not saying that these issues were not addressed, just that I missed it in my perusal.
I am most interested in this specific paper addressing the following two issues:
1. Electro-dynamic braking resulting from the interaction of the conductive materials aboard the spacecraft and solar magnetic field.
2. The variability of the flight path angles relative to Solar System Bary-center.
Your patience and direction is appreciated.
Gavilan
none of the flyby observations can be accounted in any paper
similar for Pioneer anomaly
Anderson did an analysis and failed.
similar for Pioneer anomaly
Anderson did an analysis and failed.
QUOTE (Zarkov+Mar 30 2008, 12:52 AM)
none of the flyby observations can be accounted in any paper
similar for Pioneer anomaly
(...)
As (if) a thief in the night (I) come again in order to whisper unto you that there is an "old" dismissed manuscript paper which conveys an account that may bring the insight that all are currently looking for... the understanding of the nature of gravitation. Still baffled by an "anomalous" effect attributable to retarded energy deployment in the gravitational field?
Cheers.
P.S.: A challenge: Can Gravity be an Electrostatic Force? (PDF file)
similar for Pioneer anomaly
(...)
As (if) a thief in the night (I) come again in order to whisper unto you that there is an "old" dismissed manuscript paper which conveys an account that may bring the insight that all are currently looking for... the understanding of the nature of gravitation. Still baffled by an "anomalous" effect attributable to retarded energy deployment in the gravitational field?
Cheers.
P.S.: A challenge: Can Gravity be an Electrostatic Force? (PDF file)
Topical link Ekhalom
NO ! this is the old Mercury precession explanation, retarded gravity..... no ESGT gives a very precise calculation and explanation... that can be seen in many binary systems.
NO ! this is the old Mercury precession explanation, retarded gravity..... no ESGT gives a very precise calculation and explanation... that can be seen in many binary systems.
it is natural to suspect that the system which now governs progress on matters scientific is less democratic
evidence :- ALL net science forums... they all seem to know the absolute truth on everything.... LOL, LOL
the Lorentz force law is simply incorrect. No valid results can be drawn from the logic employed. Lenz was correct... see the orbit of Earth's second Moon.
I read the last link... mixed up fantasy theories concocted with no evidence.
suffice to say gravity is the resultant of a driven spherical Poynting energy vector.. from my research and math.
As (if) a thief in the night (I) come again in order to whisper unto you that there is an "old" dismissed manuscript paper which conveys an account that may bring the insight that all are currently looking for... the understanding of the nature of gravitation. Still baffled by an "anomalous" effect attributable to retarded energy deployment in the gravitational field?
Cheers.
P.S.: A challenge: Can Gravity be an Electrostatic Force? (PDF file)
I see the early times here; in the downhill journey Newtonian Gravity is sure to take as it stands aside for the "real" explanation. We live in an Electric Universe ...
Electric Universe, YES
Newtonian gravity in amended form is a solid foundation... rock solid... primitive but accurate
Don't be fooled, all it needs is an electrodynamic theory layer
as I have done in ESGT.... all predictions are verified by observation..... no assumptions made, no slight of hand
and the math... nothing but the most accurate math possible...algebra.
QUOTE
Aspen:- if it takes time for gravitational field energy to adjust to change of relative position of two interacting bodies,
NO ! this is the old Mercury precession explanation, retarded gravity..... no ESGT gives a very precise calculation and explanation... that can be seen in many binary systems.
QUOTE (->
| QUOTE |
| Aspen:- if it takes time for gravitational field energy to adjust to change of relative position of two interacting bodies, |
NO ! this is the old Mercury precession explanation, retarded gravity..... no ESGT gives a very precise calculation and explanation... that can be seen in many binary systems.
it is natural to suspect that the system which now governs progress on matters scientific is less democratic
evidence :- ALL net science forums... they all seem to know the absolute truth on everything.... LOL, LOL
QUOTE
Every physicist well knows that the key law of electrodynamic action is that bearing the name of Lorentz. It simply has to be correct because it conforms with Einstein's theory! Yet all it tells you is that the magnetic force acting on a moving electric charge is directed at right angles to that motion. We calculate the strength of the magnetic field and know that it acts on moving charge, electric current in a conductor for example, and merely pushes it in a direction lateral to that motion.
Every physicist also knows that there is another law bearing the name of Lenz.
Every physicist also knows that there is another law bearing the name of Lenz.
the Lorentz force law is simply incorrect. No valid results can be drawn from the logic employed. Lenz was correct... see the orbit of Earth's second Moon.
I read the last link... mixed up fantasy theories concocted with no evidence.
suffice to say gravity is the resultant of a driven spherical Poynting energy vector.. from my research and math.
QUOTE (ekhalom+Mar 30 2008, 01:28 AM)
As (if) a thief in the night (I) come again in order to whisper unto you that there is an "old" dismissed manuscript paper which conveys an account that may bring the insight that all are currently looking for... the understanding of the nature of gravitation. Still baffled by an "anomalous" effect attributable to retarded energy deployment in the gravitational field?
Cheers.
P.S.: A challenge: Can Gravity be an Electrostatic Force? (PDF file)
I see the early times here; in the downhill journey Newtonian Gravity is sure to take as it stands aside for the "real" explanation. We live in an Electric Universe ...
QUOTE
the downhill journey Newtonian Gravity is sure to take
Electric Universe, YES
Newtonian gravity in amended form is a solid foundation... rock solid... primitive but accurate
Don't be fooled, all it needs is an electrodynamic theory layer
as I have done in ESGT.... all predictions are verified by observation..... no assumptions made, no slight of hand
and the math... nothing but the most accurate math possible...algebra.
QUOTE (Zarkov+Mar 30 2008, 05:24 AM)
I have done in ESGT
European Society of Gene Therapy - you need it bad sucker.
European Society of Gene Therapy - you need it bad sucker.
QUOTE (uaafanblog+Mar 30 2008, 05:13 AM)
I see the early times here; (...)
Thank you for your input; who knows if the answer comes when revising what went wrong with our assumptions in the early times of the past 20th century...
I read the last link... mixed up fantasy theories concocted with no evidence.
If we were able to meditate on how many times, in all ages through human history, words similar to those of yours were spoken against the pioneering ones who brought advancement, enlightenment and progress to the world, but who were rewarded for the most part in their own times by ingratitude, persecution and misunderstanding...
If we were able to meditate on how we shut our minds to the "rays of truth" through a mental attitude which is nothing else than the the acme of self-satisfaction and intolerance... "A little child" is the very opposite of its elders in that respect.
If we were allowed to grasp for a brief moments what is at stake with ourselves at the early stage of this new century...
Anyway, it is my last post here as it appears that certain individuals in this Science forum feel their (still) weak consciousness disturbed with my presence -- I must fight my own temptation and leave you with your own free will...
Still, (I) leave you with a poem:
Making Choices
Choose what you perceive.
Block out all the rest.
Choose what you absorb,
What you think is best.
Choose what you say and do,
What you plant as seed.
Choose what you set in motion.
Choose what powers you feed.
Those who make no choices
And leave everything to chance
By default become
Victims of circumstance.
Those who make conscious choices
And take responsibility
Will learn what choices help them
Get where they wish to be.
-- Elsa M. Glover, Professor of Physics (d.2003)
Non nobis, Domine, non nobis, sed nomini Tuo da gloriam
Thank you for your input; who knows if the answer comes when revising what went wrong with our assumptions in the early times of the past 20th century...
QUOTE (Zarkov+Mar 30 2008, 04:35 AM)
I read the last link... mixed up fantasy theories concocted with no evidence.
If we were able to meditate on how many times, in all ages through human history, words similar to those of yours were spoken against the pioneering ones who brought advancement, enlightenment and progress to the world, but who were rewarded for the most part in their own times by ingratitude, persecution and misunderstanding...
If we were able to meditate on how we shut our minds to the "rays of truth" through a mental attitude which is nothing else than the the acme of self-satisfaction and intolerance... "A little child" is the very opposite of its elders in that respect.
If we were allowed to grasp for a brief moments what is at stake with ourselves at the early stage of this new century...
Anyway, it is my last post here as it appears that certain individuals in this Science forum feel their (still) weak consciousness disturbed with my presence -- I must fight my own temptation and leave you with your own free will...
Still, (I) leave you with a poem:
Making Choices
Choose what you perceive.
Block out all the rest.
Choose what you absorb,
What you think is best.
Choose what you say and do,
What you plant as seed.
Choose what you set in motion.
Choose what powers you feed.
Those who make no choices
And leave everything to chance
By default become
Victims of circumstance.
Those who make conscious choices
And take responsibility
Will learn what choices help them
Get where they wish to be.
-- Elsa M. Glover, Professor of Physics (d.2003)
Non nobis, Domine, non nobis, sed nomini Tuo da gloriam
QUOTE (ekhalom+Mar 31 2008, 09:36 AM)
Still, (I) leave you with a poem
Just you leaving is enough.
Just you leaving is enough.
QUOTE (barakn+Mar 22 2008, 06:33 AM)
Gavilan,
The shuttle tether is a very interesting example. It had me vacillating on my position.
This comes from the bottom of a poorly-written wiki article on homopolar generators:
The statement about special relativity and a uniform magnetic field is essentially the same claim that I've been making. When applying the question "the velocity relative to what?" it becomes obvious that the tether is flying past a bunch of electrons trapped in the Earth's magnetic field (assuming an equatorial orbit so the electrons do have a degree of freedom but which is perpendicular to the tether's velocity). It is these free electrons which not only are necessary to form the return current but which also experience a Lorentz force that pushes them to one end of the tether to initiate the current in the tether in the first place.
So my position as it now stands is that there could be a small amount of force due to eddy currents and Faraday's law within conducting pieces as the satellite moves through varying magnetic fields (most B fields in space are big though so the variation doesn't occur quickly) or due to Lorentz force as it flies through uniform B fields and encounters free electrons trapped therein forming circuits which exist partially within the conductive areas and partially in free space. However, since the satellite is not likely to have a long extended shape perpendicular to the B field, I expect these currents and thus the force to also be weak. I think we may be closer to agreement, if only a tad.
And no, the homopolar generator did not come out of left field, it was mentioned on the wiki page on electrodynamic tethers. The quote above does contain at least one error, claiming Faraday's law is a cross product involving the magnetic flux vector when it should just be the magnetic field vector.
Barakn;
Thank you for your input.
Using your understanding of the electrodynamic effects of a conductor moving through a field of constant strength, I want to describe a simple experiment I witnessed many years ago. In order that I might better understand your position; I would ask you to describe your understanding in light of my observation.
A flat aluminum or copper plate was hung from a long string so that the plate acted as a bob on a pendulum. The plate was allowed to swing between the poles of a horseshoe magnet. A significant braking effect was observed as the bob swung between the poles of the magnet.
Would the same affect be observed if the bob was a sphere?
Also, I believe there to be a fundamental difference between the deflection of an electron moving between the plates of a CRT and the dynamic braking force developed in a regenerating motor of a hybrid vehicle.
Gavilan
The shuttle tether is a very interesting example. It had me vacillating on my position.
This comes from the bottom of a poorly-written wiki article on homopolar generators:
The statement about special relativity and a uniform magnetic field is essentially the same claim that I've been making. When applying the question "the velocity relative to what?" it becomes obvious that the tether is flying past a bunch of electrons trapped in the Earth's magnetic field (assuming an equatorial orbit so the electrons do have a degree of freedom but which is perpendicular to the tether's velocity). It is these free electrons which not only are necessary to form the return current but which also experience a Lorentz force that pushes them to one end of the tether to initiate the current in the tether in the first place.
So my position as it now stands is that there could be a small amount of force due to eddy currents and Faraday's law within conducting pieces as the satellite moves through varying magnetic fields (most B fields in space are big though so the variation doesn't occur quickly) or due to Lorentz force as it flies through uniform B fields and encounters free electrons trapped therein forming circuits which exist partially within the conductive areas and partially in free space. However, since the satellite is not likely to have a long extended shape perpendicular to the B field, I expect these currents and thus the force to also be weak. I think we may be closer to agreement, if only a tad.
And no, the homopolar generator did not come out of left field, it was mentioned on the wiki page on electrodynamic tethers. The quote above does contain at least one error, claiming Faraday's law is a cross product involving the magnetic flux vector when it should just be the magnetic field vector.
Barakn;
Thank you for your input.
Using your understanding of the electrodynamic effects of a conductor moving through a field of constant strength, I want to describe a simple experiment I witnessed many years ago. In order that I might better understand your position; I would ask you to describe your understanding in light of my observation.
A flat aluminum or copper plate was hung from a long string so that the plate acted as a bob on a pendulum. The plate was allowed to swing between the poles of a horseshoe magnet. A significant braking effect was observed as the bob swung between the poles of the magnet.
Would the same affect be observed if the bob was a sphere?
Also, I believe there to be a fundamental difference between the deflection of an electron moving between the plates of a CRT and the dynamic braking force developed in a regenerating motor of a hybrid vehicle.
Gavilan
QUOTE (Gavilan+Apr 1 2008, 03:49 AM)
Barakn;
Thank you for your input.
Using your understanding of the electrodynamic effects of a conductor moving through a field of constant strength, I want to describe a simple experiment I witnessed many years ago. In order that I might better understand your position; I would ask you to describe your understanding in light of my observation.
A flat aluminum or copper plate was hung from a long string so that the plate acted as a bob on a pendulum. The plate was allowed to swing between the poles of a horseshoe magnet. A significant braking effect was observed as the bob swung between the poles of the magnet.
Would the same affect be observed if the bob was a sphere?
Also, I believe there to be a fundamental difference between the deflection of an electron moving between the plates of a CRT and the dynamic braking force developed in a regenerating motor of a hybrid vehicle.
Gavilan
The pendulum and horseshoe magnet is another demonstration of Faraday's law. The amount of magnetic flux through the plate varies greatly when the plate is between the poles vs. when it has swung further away. This induces eddy currents. A spherical bob would also work, but if it is the same mass as the plate it wouldn't be as effective because its cross section perpendicular to the magnetic field would be smaller.
The electron in a CRT will follow the Lorentz law. Regenerative motors use Faraday's, so I'd agree there is a fundamental difference.
Thank you for your input.
Using your understanding of the electrodynamic effects of a conductor moving through a field of constant strength, I want to describe a simple experiment I witnessed many years ago. In order that I might better understand your position; I would ask you to describe your understanding in light of my observation.
A flat aluminum or copper plate was hung from a long string so that the plate acted as a bob on a pendulum. The plate was allowed to swing between the poles of a horseshoe magnet. A significant braking effect was observed as the bob swung between the poles of the magnet.
Would the same affect be observed if the bob was a sphere?
Also, I believe there to be a fundamental difference between the deflection of an electron moving between the plates of a CRT and the dynamic braking force developed in a regenerating motor of a hybrid vehicle.
Gavilan
The pendulum and horseshoe magnet is another demonstration of Faraday's law. The amount of magnetic flux through the plate varies greatly when the plate is between the poles vs. when it has swung further away. This induces eddy currents. A spherical bob would also work, but if it is the same mass as the plate it wouldn't be as effective because its cross section perpendicular to the magnetic field would be smaller.
The electron in a CRT will follow the Lorentz law. Regenerative motors use Faraday's, so I'd agree there is a fundamental difference.
Doh. Just caught my own mistake. Should have said "Lenz's law" and not "Lorentz law."
Just caught my own mistake. Should have said "Lenz's law" and not "Lorentz law."
thanks
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