if life every existed on mars could this event be sufficent to allow debris to reach the earth, debris that could carry life?
this impact is thought to of occurred 4 billion years ago and life on earth seems to of got going on earth 3.7 billion years or so. coincidence ? discuss
The idea of massive impact seems far fetched kjw. Where are the results of impact? We are talking topography here which always existed on Mars vs. an event dichotomizing the planet. I'll go with natural topography. 
QUOTE (midwestern+Jun 30 2008, 06:13 AM)
The idea of massive impact seems far fetched kjw
Yeah, so far fetched that a massive impact went and made a moon right next to our planet.
Yeah, so far fetched that a massive impact went and made a moon right next to our planet.
Absolutely ridiculous stuff N.O.M.. 
My apologies for drifting away from the initial question about spreading life...
This impact is told as a new observation, but it's nothing of an observation. It's just a computer model telling that an impact may reproduce some of the observations we make.
You can observe that the lower northern plains of Mars
http://www.google.com/mars
carry fewer impact craters than the southern altiplano does. Why, if this dichotomy results from such an ancient event?
Earth also had one single continent (Pangea) in the past without needing a cosmic impact to explain it. This was in recent geological times, more compatible with crater abundance on Mars.
I prefer Mars' dichotomy to be the result of more recent tectonic activity: oceanic-type lava flows pushing all continental crust together at some time of history, like it did on Earth at the time of Pangea.
The same holds for our Moon: its invisible side carries far less craters, just as its "seas" (its plains) do. Again a relatively recent global pattern.
This impact is told as a new observation, but it's nothing of an observation. It's just a computer model telling that an impact may reproduce some of the observations we make.
You can observe that the lower northern plains of Mars
http://www.google.com/mars
carry fewer impact craters than the southern altiplano does. Why, if this dichotomy results from such an ancient event?
Earth also had one single continent (Pangea) in the past without needing a cosmic impact to explain it. This was in recent geological times, more compatible with crater abundance on Mars.
I prefer Mars' dichotomy to be the result of more recent tectonic activity: oceanic-type lava flows pushing all continental crust together at some time of history, like it did on Earth at the time of Pangea.
The same holds for our Moon: its invisible side carries far less craters, just as its "seas" (its plains) do. Again a relatively recent global pattern.
I must not follow the literature closely enough... Where was this published?
Anyway, 6 to 10 km/s sounds very slow for an object hitting Mars. Even an object that big would be going significantly faster when falling towards the planet, especially when it came from outside of orbit.
Of course, that's not exactly my field of astronomy, I'm more of a distant-galaxy astronomer, so I'll take my peers' word for it that it is actually possible to liquify one half of the planet without affecting the other half.
Personally, geologic activity sounds lot more logical. If the shelves move away from the "clean" hemisphere and towards the mountainous one, it would probably look the same.
Anyway, 6 to 10 km/s sounds very slow for an object hitting Mars. Even an object that big would be going significantly faster when falling towards the planet, especially when it came from outside of orbit.
Of course, that's not exactly my field of astronomy, I'm more of a distant-galaxy astronomer, so I'll take my peers' word for it that it is actually possible to liquify one half of the planet without affecting the other half.
Personally, geologic activity sounds lot more logical. If the shelves move away from the "clean" hemisphere and towards the mountainous one, it would probably look the same.
Glacial carve created the bodies of water on Mars. A huge, sudden impact flattening one side of Mars didn't create the water appearing on the planet. 
QUOTE (Enthalpy+Jun 30 2008, 09:07 AM)
You can observe that the lower northern plains of Mars
http://www.google.com/mars
carry fewer impact craters than the southern altiplano does. Why, if this dichotomy results from such an ancient event?
With such a big hole, things tend to fill it, burying existing craters and creating a surface material that doesn't hold the shape of new impacts so well. In particular some believe there was a northern ocean filling the basin, which if it existed would have coated everything with a thick blanket of settled material. There's also the less controversial objects like the volcanoes which tend to congregate around the edges of the basin and periodically flood its sides with lava. Then of course there's the fact that incoming impactors would find not only a thicker atmospheric profile over the basin but would encounter a higher surface pressure than anywhere else - the resultant craters would be smaller than had they been made elsewhere. Also note that there's a large area we know virtually nothing about because it's hidden under the polar ice cap, and the ice cap itself would protect the surface below from impacts. Then also consider the flattened surface and slightly weakened gravity in that area - impacts would have slightly less energy and shallow angle impactors would be slightly more likely to miss altogether. And finally don't forget the non-stop wind and global dust storms. Even now the northern basin is filling in.
Most geologists don't see any evidence of any sort of plate tectonics, although some feel the Valles Marineris might be a failed rift.
http://www.google.com/mars
carry fewer impact craters than the southern altiplano does. Why, if this dichotomy results from such an ancient event?
With such a big hole, things tend to fill it, burying existing craters and creating a surface material that doesn't hold the shape of new impacts so well. In particular some believe there was a northern ocean filling the basin, which if it existed would have coated everything with a thick blanket of settled material. There's also the less controversial objects like the volcanoes which tend to congregate around the edges of the basin and periodically flood its sides with lava. Then of course there's the fact that incoming impactors would find not only a thicker atmospheric profile over the basin but would encounter a higher surface pressure than anywhere else - the resultant craters would be smaller than had they been made elsewhere. Also note that there's a large area we know virtually nothing about because it's hidden under the polar ice cap, and the ice cap itself would protect the surface below from impacts. Then also consider the flattened surface and slightly weakened gravity in that area - impacts would have slightly less energy and shallow angle impactors would be slightly more likely to miss altogether. And finally don't forget the non-stop wind and global dust storms. Even now the northern basin is filling in.
QUOTE
Earth also had one single continent (Pangea) in the past without needing a cosmic impact to explain it. This was in recent geological times, more compatible with crater abundance on Mars.
I prefer Mars' dichotomy to be the result of more recent tectonic activity: oceanic-type lava flows pushing all continental crust together at some time of history, like it did on Earth at the time of Pangea.
Did Pangea cover more than 50% of the Earth's surface?I prefer Mars' dichotomy to be the result of more recent tectonic activity: oceanic-type lava flows pushing all continental crust together at some time of history, like it did on Earth at the time of Pangea.
Most geologists don't see any evidence of any sort of plate tectonics, although some feel the Valles Marineris might be a failed rift.
QUOTE (->
| QUOTE |
| Earth also had one single continent (Pangea) in the past without needing a cosmic impact to explain it. This was in recent geological times, more compatible with crater abundance on Mars. I prefer Mars' dichotomy to be the result of more recent tectonic activity: oceanic-type lava flows pushing all continental crust together at some time of history, like it did on Earth at the time of Pangea. |
Did Pangea cover more than 50% of the Earth's surface?
Most geologists don't see any evidence of any sort of plate tectonics, although some feel the Valles Marineris might be a failed rift.
The same holds for our Moon: its invisible side carries far less craters, just as its "seas" (its plains) do. Again a relatively recent global pattern.
It doesn't have less craters. The craters that are there just didn't punch down far enough to release magma and so didn't form maria. The crust on the far side is simply deeper because that was the side that formed facing away from Earth.
http://apod.nasa.gov/apod/ap981008.html
Most geologists don't see any evidence of any sort of plate tectonics, although some feel the Valles Marineris might be a failed rift.
The same holds for our Moon: its invisible side carries far less craters, just as its "seas" (its plains) do. Again a relatively recent global pattern.
It doesn't have less craters. The craters that are there just didn't punch down far enough to release magma and so didn't form maria. The crust on the far side is simply deeper because that was the side that formed facing away from Earth.
http://apod.nasa.gov/apod/ap981008.html
Barakn, how do you know gravity is weakened in the supposed area mentioned? Gravity should be constant.
QUOTE (midwestern+Jun 30 2008, 02:58 PM)
Barakn, how do you know gravity is weakened in the supposed area mentioned? Gravity should be constant.
Gravity should be constant? Who says? Now if Mars had complete spherical symmetry then at any given altitude the gravity should be constant over any point on its surface. But it's not spherically symmetrical. Gravity is associated with mass and Mars is missing some mass on its northern end. Neither are the Earth nor Moon perfectly spherically symmetrical. In fact, investigating the local strength of gravity is a unique way of non-invasively probing under the surface http://www.csr.utexas.edu/grace/gravity/
And then here's the part where I eat crow. Mars doesn't have much of a negative gravity anomaly at its north pole, and neither do a lot of other craters, on Mars or the Moon. The craters are missing mass because they've been excavated, but that is apparently more than made up in some cases by the presence of very dense materials like lava flows that infill the bottoms of the craters.
http://photojournal.jpl.nasa.gov/catalog/PIA02817
http://home.netcom.com/~sbyers11/moongrv2.gif
Gravity should be constant? Who says? Now if Mars had complete spherical symmetry then at any given altitude the gravity should be constant over any point on its surface. But it's not spherically symmetrical. Gravity is associated with mass and Mars is missing some mass on its northern end. Neither are the Earth nor Moon perfectly spherically symmetrical. In fact, investigating the local strength of gravity is a unique way of non-invasively probing under the surface http://www.csr.utexas.edu/grace/gravity/
And then here's the part where I eat crow. Mars doesn't have much of a negative gravity anomaly at its north pole, and neither do a lot of other craters, on Mars or the Moon. The craters are missing mass because they've been excavated, but that is apparently more than made up in some cases by the presence of very dense materials like lava flows that infill the bottoms of the craters.
http://photojournal.jpl.nasa.gov/catalog/PIA02817
http://home.netcom.com/~sbyers11/moongrv2.gif
Thanks for your honesty barakn.
QUOTE (midwestern+Jul 1 2008, 01:19 PM)
Thanks for your honesty barakn.
You're welcome.
One final point: since the Martian north pole doesn't have a large negative gravity anomaly, that is actually good evidence for a crater that partially infilled with lava.
You're welcome.
One final point: since the Martian north pole doesn't have a large negative gravity anomaly, that is actually good evidence for a crater that partially infilled with lava.
There is a book called The Mars Mystery.
It talks of Mars being hit something massive at some time.
Mars is not perfectly sperical and is more like the shape of an orange with the peel taken off the top half.
Also opposite some bulge is an impact crater.
That is the author thinks that Mars was hit in the south and that knocked the norths crust off.
It talks of Mars being hit something massive at some time.
Mars is not perfectly sperical and is more like the shape of an orange with the peel taken off the top half.
Also opposite some bulge is an impact crater.
That is the author thinks that Mars was hit in the south and that knocked the norths crust off.
While it's possible that Mars was hit by a large object, it isn't the only way to explain the surface. There are several problems with both tectonics and impact hypothesis.
Both are really hard determine without actually drilling a few large holes and looking at some rock cores, and since that's not going to happen any time soon, we're stuck with just looking at it.
Backyard astronomy* isn't exactly my specialty, but here's a little thing to consider. An object large enough to deal this much damage to Mars would probably come from pretty far out, if it's orbit was erratic enough to hit another planet.
Now, compared to the rest of solar system, and especially the outer solar system, Mars has a tiny gravity well. An extrasolar object has a pretty small chance of hitting Mars, but of course, that doesn't mean it didn't happen
*derogatory term for the astronomy that deals with the inner solar system
Both are really hard determine without actually drilling a few large holes and looking at some rock cores, and since that's not going to happen any time soon, we're stuck with just looking at it.
Backyard astronomy* isn't exactly my specialty, but here's a little thing to consider. An object large enough to deal this much damage to Mars would probably come from pretty far out, if it's orbit was erratic enough to hit another planet.
Now, compared to the rest of solar system, and especially the outer solar system, Mars has a tiny gravity well. An extrasolar object has a pretty small chance of hitting Mars, but of course, that doesn't mean it didn't happen
*derogatory term for the astronomy that deals with the inner solar system
Buttershug, your explanation of the topography of Mars is a stretch. Mars was hit in the south and the north had it's crust knocked off? What kind of a sophomoric explanation is that Buttershug? 
QUOTE (midwestern+Jul 2 2008, 07:06 PM)
Buttershug, your explanation of the topography of Mars is a stretch. Mars was hit in the south and the north had it's crust knocked off? What kind of a sophomoric explanation is that Buttershug?
It's not my explanaition, it's the authors.
And if you are hit in the front of you head with a shot gun blast, the back of your head gets blasted off.
Maybe you should get your mother to buy you a Newton's Cradle.
If you practice you can actually improve your imagination.
And didn't Levy-Shoemaker prove that sometimes comets hit planets?
It's not my explanaition, it's the authors.
And if you are hit in the front of you head with a shot gun blast, the back of your head gets blasted off.
Maybe you should get your mother to buy you a Newton's Cradle.
If you practice you can actually improve your imagination.
And didn't Levy-Shoemaker prove that sometimes comets hit planets?
My imagination is fine and the author is the one to blame here, I guess. Sounds as though you do believe in him. Sorry, but I tend to believe natural topographical phenomenon shaped the surface of the planet. 
QUOTE (Alcari+Jul 2 2008, 04:08 AM)
Backyard astronomy* isn't exactly my specialty, but here's a little thing to consider. An object large enough to deal this much damage to Mars would probably come from pretty far out, if it's orbit was erratic enough to hit another planet.
Nope. The north pole basin is the oldest feature on Mars, arising during the age when numerous planetesimals, leftovers from planetary construction, were still wandering the inner solar system. One of these would collide with the Earth and form the Moon.
Nope. The north pole basin is the oldest feature on Mars, arising during the age when numerous planetesimals, leftovers from planetary construction, were still wandering the inner solar system. One of these would collide with the Earth and form the Moon.
QUOTE (buttershug+Jul 2 2008, 03:05 PM)
And if you are hit in the front of you head with a shot gun blast, the back of your head gets blasted off.
Your head, I would hope, is not as dense as shotgun pellets. Not so with a planet\planetesimal collision.
Your head, I would hope, is not as dense as shotgun pellets. Not so with a planet\planetesimal collision.
QUOTE (barakn+Jul 2 2008, 10:17 PM)
Your head, I would hope, is not as dense as shotgun pellets. Not so with a planet\planetesimal collision.
The balls in a Newton's cradle are more dense than planets.
The balls in a Newton's cradle are more dense than planets.
You lose the argument buttershug. Barakn and I agree the North was not 'hit' by a stunning force.
QUOTE (buttershug+Jul 2 2008, 05:12 PM)
The balls in a Newton's cradle are more dense than planets.
The balls in a Newton's cradle don't melt when they run into each other. The balls in a Newton's cradle are very specifically made to to have identical masses. Your analogy is false.
The balls in a Newton's cradle don't melt when they run into each other. The balls in a Newton's cradle are very specifically made to to have identical masses. Your analogy is false.
QUOTE (barakn+Jul 4 2008, 04:18 AM)
The balls in a Newton's cradle don't melt when they run into each other. The balls in a Newton's cradle are very specifically made to to have identical masses. Your analogy is false.
Who's talking about melting?
I'm talking about momentum going through a solid object and causeing material to be ejected from the other side.
How do you explain the Tharsus bulge with a huge impact crater on it's anit-pode?
It's not a basin on the north pole. It's the entire "top" of Mars that is missing.
And there are two other bulges with craters a their ani-podes.
I believe you can knock crud from the inside of a pipe by hitting the outside of the pipe.
@Midwestern, no you lose because you have learned nothing. In the 0.9r thread I won because I learned that rational numbers are infinitely countable.
Who's talking about melting?
I'm talking about momentum going through a solid object and causeing material to be ejected from the other side.
How do you explain the Tharsus bulge with a huge impact crater on it's anit-pode?
It's not a basin on the north pole. It's the entire "top" of Mars that is missing.
And there are two other bulges with craters a their ani-podes.
I believe you can knock crud from the inside of a pipe by hitting the outside of the pipe.
@Midwestern, no you lose because you have learned nothing. In the 0.9r thread I won because I learned that rational numbers are infinitely countable.
QUOTE (buttershug+Jul 4 2008, 03:08 PM)
Who's talking about melting?
I'm talking about momentum going through a solid object and causeing material to be ejected from the other side.
I'm talking about melting because of the extreme energy of the collision, and also because early Mars certainly had a molten core. Have you ever studied what happens to waves traveling through planets? Those initially headed straight down curve away from the core, and a liquid core blocks s-waves entirely. This spreads the energy and momentum of the impact throughout the planet rather than sending it straight on through to the other side.
How do you explain the Tharsus bulge with a huge impact crater on it's anit-pode?
It's not a basin on the north pole. It's the entire "top" of Mars that is missing.
And there are two other bulges with craters a their ani-podes.
That's odd. Your original claim was that the north pole basin was an impact antipode. Now you're saying that volcanic regions or bulges are at antipodes. Apparently your theory is flexible enough that either bulges, volcanoes, or depressions can appear at the antipode, depending on your whim.
That's odd. Your original claim was that the north pole basin was an impact antipode. Now you're saying that volcanic regions or bulges are at antipodes. Apparently your theory is flexible enough that either bulges, volcanoes, or depressions can appear at the antipode, depending on your whim.
I believe you can knock crud from the inside of a pipe by hitting the outside of the pipe.
Yet another useless analogy.
LOL, as if
yes all special cases, even our moon, and what about Jupiter's and all the rest
all captured...LOL.... totally idiotic
You humans are sooooooooooooooo weird !!!!!!
and lenz's Law is paramount... LOL
you have no idea
Other than everything you just wrote.
We've got thick continents and a thin ocean crust (and Hawaii smack in the middle of the Pacific) and vulcanism on the other side of the Earth (the mid-Atlantic ridge).
And they've got a gravitational anomaly, thick and thin crust, but no ocean.
Looks to me like Mars hit Earth, left us the moon close-in, and scattered debris which *might've* formed a moon for Mars if Mars had an ocean or some other tidal forces to exert on the asteroid belt to collect the farther-out debris into one solid object.
Heat makes steam, but steam cools even in space and returns to the body with the deepest gravitational well (that'd be Earth), where it makes weather which makes everything almost round and smooth.
Just my two cents, I'm not trying to get into a catfight over this.
I'm talking about momentum going through a solid object and causeing material to be ejected from the other side.
I'm talking about melting because of the extreme energy of the collision, and also because early Mars certainly had a molten core. Have you ever studied what happens to waves traveling through planets? Those initially headed straight down curve away from the core, and a liquid core blocks s-waves entirely. This spreads the energy and momentum of the impact throughout the planet rather than sending it straight on through to the other side.
QUOTE
How do you explain the Tharsus bulge with a huge impact crater on it's anit-pode?
It's not a basin on the north pole. It's the entire "top" of Mars that is missing.
And there are two other bulges with craters a their ani-podes.
That's odd. Your original claim was that the north pole basin was an impact antipode. Now you're saying that volcanic regions or bulges are at antipodes. Apparently your theory is flexible enough that either bulges, volcanoes, or depressions can appear at the antipode, depending on your whim.
QUOTE (->
| QUOTE |
How do you explain the Tharsus bulge with a huge impact crater on it's anit-pode? It's not a basin on the north pole. It's the entire "top" of Mars that is missing. And there are two other bulges with craters a their ani-podes. |
That's odd. Your original claim was that the north pole basin was an impact antipode. Now you're saying that volcanic regions or bulges are at antipodes. Apparently your theory is flexible enough that either bulges, volcanoes, or depressions can appear at the antipode, depending on your whim.
I believe you can knock crud from the inside of a pipe by hitting the outside of the pipe.
Yet another useless analogy.
Looks like everything happened 4 billion years ago !
LOL
Now Mars has two moons... and they came from Mars, so one would expect "holes" in the crust of mars... some get filled others don't, depending upon the state of the core.
Earth has the pacific.....
In general "planetary sized bodies do not collide, and this is described by Lenz's Law.
Earth has another "moon" that just shuttles back and forth in a horseshoe orbit.... Lenz's law is very active there.
Fancy hanging all your hopes on one theory !
It like trying to fit a size 12 foot into a size 2, which is rather foolish
These 'theorists' are going to have egg all over their faces one day...
LOL
LOL
Now Mars has two moons... and they came from Mars, so one would expect "holes" in the crust of mars... some get filled others don't, depending upon the state of the core.
Earth has the pacific.....
In general "planetary sized bodies do not collide, and this is described by Lenz's Law.
Earth has another "moon" that just shuttles back and forth in a horseshoe orbit.... Lenz's law is very active there.
Fancy hanging all your hopes on one theory !
It like trying to fit a size 12 foot into a size 2, which is rather foolish
These 'theorists' are going to have egg all over their faces one day...
LOL
QUOTE (Zarkov+Jul 4 2008, 06:16 PM)
Now Mars has two moons... and they came from Mars, so one would expect "holes" in the crust of mars... some get filled others don't, depending upon the state of the core.
No, the moons were captured. If you ever bothered to look at them compared to Mars you'd see they're much darker and not nearly so red. Not that you'd ever bother.
Lenz's law has absolutely nothing whatsoever to do with gravity or planetary collisions, and you are an idiot for trying to make the connection.
No, the moons were captured. If you ever bothered to look at them compared to Mars you'd see they're much darker and not nearly so red. Not that you'd ever bother.
QUOTE
In general "planetary sized bodies do not collide, and this is described by Lenz's Law.
Earth has another "moon" that just shuttles back and forth in a horseshoe orbit.... Lenz's law is very active there.
Earth has another "moon" that just shuttles back and forth in a horseshoe orbit.... Lenz's law is very active there.
Lenz's law has absolutely nothing whatsoever to do with gravity or planetary collisions, and you are an idiot for trying to make the connection.
QUOTE
the moons were captured.
LOL, as if
yes all special cases, even our moon, and what about Jupiter's and all the rest
all captured...LOL.... totally idiotic
You humans are sooooooooooooooo weird !!!!!!
and lenz's Law is paramount... LOL
you have no idea
QUOTE (barakn+Jul 4 2008, 11:55 PM)
I'm talking about melting because of the extreme energy of the collision, and also because early Mars certainly had a molten core. Have you ever studied what happens to waves traveling through planets? Those initially headed straight down curve away from the core, and a liquid core blocks s-waves entirely. This spreads the energy and momentum of the impact throughout the planet rather than sending it straight on through to the other side.
That's odd. Your original claim was that the north pole basin was an impact antipode. Now you're saying that volcanic regions or bulges are at antipodes. Apparently your theory is flexible enough that either bulges, volcanoes, or depressions can appear at the antipode, depending on your whim.
Yet another useless analogy.
It's not my theory and I was saying an impact crator on one side and a missing mass around a bulge on the other side.
Where the basin is, does not look like an impact crater, and has a bulge in the middle. (or three bulges it's been a while since I read the book.(and I was was laughing at half of it))
That's odd. Your original claim was that the north pole basin was an impact antipode. Now you're saying that volcanic regions or bulges are at antipodes. Apparently your theory is flexible enough that either bulges, volcanoes, or depressions can appear at the antipode, depending on your whim.
Yet another useless analogy.
It's not my theory and I was saying an impact crator on one side and a missing mass around a bulge on the other side.
Where the basin is, does not look like an impact crater, and has a bulge in the middle. (or three bulges it's been a while since I read the book.(and I was was laughing at half of it))
Actually, it's a pretty decent theory, backed by what bullets do to bodies. Small entry wound, large exit wound.
Interesting idea, Alcari!
Interesting idea, Alcari!
QUOTE (wcelliott+Jul 5 2008, 08:36 PM)
Actually, it's a pretty decent theory, backed by what bullets do to bodies. Small entry wound, large exit wound.
Interesting idea, Alcari!
It's a crap theory based on an analogy that's worthless.
Interesting idea, Alcari!
It's a crap theory based on an analogy that's worthless.
Buttershug, I lose because I what? Where in the world did you come up with that one! How strange. 
Barakn is mint on his discussion after reading the thread. Good job.
Good job.
This thread is pure sophistry... as if any one on Earth was there to witness anything about the history of Mars !!
tis a joke, eh ????
or R U all complete and utter imbaciles
Your theories, no THEIR theories (y'all have no theories !!! LOL ) are all pure conjecture... and very poorly thought through ones at that.
Earthlings you are a very curious species !!!
LOL
tis a joke, eh ????
or R U all complete and utter imbaciles
Your theories, no THEIR theories (y'all have no theories !!! LOL ) are all pure conjecture... and very poorly thought through ones at that.
Earthlings you are a very curious species !!!
LOL
QUOTE (Zarkov+Jul 6 2008, 03:44 PM)
This thread is pure sophistry... as if any one on Earth was there to witness anything about the history of Mars !!
The history of Mars is written in its rocks. If you're unable to read it, that's your problem.
The history of Mars is written in its rocks. If you're unable to read it, that's your problem.
The prevailing theory is that Earth's moon was created when Earth was struck by a Mars-sized object, about 4 billion years ago.
QUOTE (midwestern+Jul 6 2008, 05:55 PM)
Buttershug, I lose because I what? Where in the world did you come up with that one! How strange.
You lose because you don't gain.
If you go to work and don't get anything for it, wouldn't you consider that losing?
You lose because you don't gain.
If you go to work and don't get anything for it, wouldn't you consider that losing?
QUOTE (Zarkov+Jul 6 2008, 09:44 PM)
This thread is pure sophistry... as if any one on Earth was there to witness anything about the history of Mars !!
tis a joke, eh ????
or R U all complete and utter imbaciles
Your theories, no THEIR theories (y'all have no theories !!! LOL ) are all pure conjecture... and very poorly thought through ones at that.
Earthlings you are a very curious species !!!
LOL
Are you actually claiming to be a non-earthling?
tis a joke, eh ????
or R U all complete and utter imbaciles
Your theories, no THEIR theories (y'all have no theories !!! LOL ) are all pure conjecture... and very poorly thought through ones at that.
Earthlings you are a very curious species !!!
LOL
Are you actually claiming to be a non-earthling?
It seems to me this impact scenario is unlikely. Where's the relatively large moon that should've subsequently formed?
It figures that a thread like this would attract all of the idiots of the forum.
1) The bulge in the middle.
Gee. I wonder how that got there - could it possibly be that Gravity has a tendency to pull liquids into a sphere. Now I wonder where I could possibly find evidence for a silly idea like that - hmmm, hey look, the planets are round, and they were fluid...
2) The lack of a large moon.
Frankly, the statement is just preposterous. If a large impactor were to create a moon every time it hit another body, then where's the large moon around Mercury? (Caloris basin).
Where's the large moon around Mimas (Herschel impact crater - which if scaled up to earth, would be larger then canada).
Where's the satelite around Vesta (an asteroid that has a crater on it comparable to the one being proposed for Mars User posted image: User posted image).
3) The massive impactor theory for the earths moon, as far as that goes, a recent article has cast some doubt on that theory, apparently some recent research suggests that although below the detection levels of previous experiments, the volatile content of the moons surface is too high to support that hypothesis.
Seriously people...
1) The bulge in the middle.
Gee. I wonder how that got there - could it possibly be that Gravity has a tendency to pull liquids into a sphere. Now I wonder where I could possibly find evidence for a silly idea like that - hmmm, hey look, the planets are round, and they were fluid...
2) The lack of a large moon.
Frankly, the statement is just preposterous. If a large impactor were to create a moon every time it hit another body, then where's the large moon around Mercury? (Caloris basin).
Where's the large moon around Mimas (Herschel impact crater - which if scaled up to earth, would be larger then canada).
Where's the satelite around Vesta (an asteroid that has a crater on it comparable to the one being proposed for Mars User posted image: User posted image).
3) The massive impactor theory for the earths moon, as far as that goes, a recent article has cast some doubt on that theory, apparently some recent research suggests that although below the detection levels of previous experiments, the volatile content of the moons surface is too high to support that hypothesis.
Seriously people...
let us work on a checklist of required evidence that would support the opening question.
1) sample of mars material making it to earth - i understand this is generally accepted as being true http://www2.jpl.nasa.gov/snc/
2) life forms capable of surviving conditions experienced during ejection of material from Mars, journey through space, entry into earths atmosphere - there is a lot to discuss here. the ejection conditions would be very harsh on life. does anyone know of experiments conducted that test this part? the survival in space is shown to be possible for lichen is there other such experiments?
3) evidence of life on mars four billion years ago. this is a missing piece of evidence.
what else would we need to have a sound theory?
1) sample of mars material making it to earth - i understand this is generally accepted as being true http://www2.jpl.nasa.gov/snc/
2) life forms capable of surviving conditions experienced during ejection of material from Mars, journey through space, entry into earths atmosphere - there is a lot to discuss here. the ejection conditions would be very harsh on life. does anyone know of experiments conducted that test this part? the survival in space is shown to be possible for lichen is there other such experiments?
3) evidence of life on mars four billion years ago. this is a missing piece of evidence.
what else would we need to have a sound theory?
The thing that occurs to me is that the collision with a Mars-sized object that formed our moon *might've* been a collision with Mars, itself, leaving it's top sheared off.
Planets aren't round because they're liquid, they're round because if there's anything on the edge of a large cliff, then it tends to fall over the edge, filling things like impact craters. Normal weathering process. Landslides, etc.
The bulge in earth is due to the fact that gravity is partially reduced due to centripetal force (normally called "centrifugal force").
If the Earth's moon were caused by a collision with a "Mars-sized object", what other Mars'-sized object is there in this solar system other than Mars?
Planets aren't round because they're liquid, they're round because if there's anything on the edge of a large cliff, then it tends to fall over the edge, filling things like impact craters. Normal weathering process. Landslides, etc.
The bulge in earth is due to the fact that gravity is partially reduced due to centripetal force (normally called "centrifugal force").
If the Earth's moon were caused by a collision with a "Mars-sized object", what other Mars'-sized object is there in this solar system other than Mars?
QUOTE (wcelliott+Jul 15 2008, 12:23 PM)
The thing that occurs to me is that the collision with a Mars-sized object that formed our moon *might've* been a collision with Mars, itself, leaving it's top sheared off.
Planets aren't round because they're liquid, they're round because if there's anything on the edge of a large cliff, then it tends to fall over the edge, filling things like impact craters. Normal weathering process. Landslides, etc.
The bulge in earth is due to the fact that gravity is partially reduced due to centripetal force (normally called "centrifugal force").
If the Earth's moon were caused by a collision with a "Mars-sized object", what other Mars'-sized object is there in this solar system other than Mars?
You're missing the point.
Planets are round because they're at hydrostatic equilibrium, because the self gravitation of the planet can overcome the rigid forces that hold it together.
But tell me, 4 billion years ago, what, precisely, do you think was under the crust of Mars?
Magma maybe? Which is what? A Liquid (at some depths) and flows in a fluid, plastic manner at most depths.
So, my statement stands true.
Planets aren't round because they're liquid, they're round because if there's anything on the edge of a large cliff, then it tends to fall over the edge, filling things like impact craters. Normal weathering process. Landslides, etc.
The bulge in earth is due to the fact that gravity is partially reduced due to centripetal force (normally called "centrifugal force").
If the Earth's moon were caused by a collision with a "Mars-sized object", what other Mars'-sized object is there in this solar system other than Mars?
You're missing the point.
Planets are round because they're at hydrostatic equilibrium, because the self gravitation of the planet can overcome the rigid forces that hold it together.
But tell me, 4 billion years ago, what, precisely, do you think was under the crust of Mars?
Magma maybe? Which is what? A Liquid (at some depths) and flows in a fluid, plastic manner at most depths.
So, my statement stands true.
Trippy, I think you're missing my point - Gravity over the course of 4 billion years doesn't *need* to act on a liquid to render an approximation of a sphere. If Mars were made entirely of gravel, it'd still be spherical just due to the fact that things fall down, but never up.
The crust of the Earth is fairly thin, compared to its molten core, but that doesn't keep the crust from being of radically different thicknesses, ocean versus land.
As far as large moons go, ours is the exception, not the rule. Our moon is massive compared to the size of the Earth, whereas the moons of all the other planets are tiny in comparison (Pluto and Charon notwithstanding).
There is a viable argument to be made that Earth and Mars collided 4 billion years ago, leaving our moon for us and leaving a lot of debris that we call "the asteroid belt" just outside Mars' orbit.
Now whether this left behind something that sparked life on earth (or vice-versa) is anybody's guess.
Lichen can survive in space, and one of the Russian space station Mir's problems was that it had mold growing on its outside, in space.
The crust of the Earth is fairly thin, compared to its molten core, but that doesn't keep the crust from being of radically different thicknesses, ocean versus land.
As far as large moons go, ours is the exception, not the rule. Our moon is massive compared to the size of the Earth, whereas the moons of all the other planets are tiny in comparison (Pluto and Charon notwithstanding).
There is a viable argument to be made that Earth and Mars collided 4 billion years ago, leaving our moon for us and leaving a lot of debris that we call "the asteroid belt" just outside Mars' orbit.
Now whether this left behind something that sparked life on earth (or vice-versa) is anybody's guess.
Lichen can survive in space, and one of the Russian space station Mir's problems was that it had mold growing on its outside, in space.
QUOTE (wcelliott+Jul 15 2008, 12:23 PM)
If the Earth's moon were caused by a collision with a "Mars-sized object", what other Mars'-sized object is there in this solar system other than Mars?
The Moon IS what was left after the Mars-sized object hit the Earth, angular momentum and all.
The Moon IS what was left after the Mars-sized object hit the Earth, angular momentum and all.
QUOTE (wcelliott+Jul 15 2008, 02:16 PM)
Trippy, I think you're missing my point - Gravity over the course of 4 billion years doesn't *need* to act on a liquid to render an approximation of a sphere. If Mars were made entirely of gravel, it'd still be spherical just due to the fact that things fall down, but never up.
The crust of the Earth is fairly thin, compared to its molten core, but that doesn't keep the crust from being of radically different thicknesses, ocean versus land.
As far as large moons go, ours is the exception, not the rule. Our moon is massive compared to the size of the Earth, whereas the moons of all the other planets are tiny in comparison (Pluto and Charon notwithstanding).
There is a viable argument to be made that Earth and Mars collided 4 billion years ago, leaving our moon for us and leaving a lot of debris that we call "the asteroid belt" just outside Mars' orbit.
Now whether this left behind something that sparked life on earth (or vice-versa) is anybody's guess.
Lichen can survive in space, and one of the Russian space station Mir's problems was that it had mold growing on its outside, in space.
No, I understood what you were saying, and I agree, and it would be relevant if we were talking about (for example) Cere's, however my contention is it's irrelevant, and my point remains the same - that the presence of the 'mound in the middle' is the result of fluid flow - whether it be plastic, or as a rubble pile, due to self gravitation, and doesn't preclude the possibility of the martian northern plains being caused by a massive impact.
The 'mound in the middle' is formed by the mantle material 'flowing back into place'.
I don't get why you're arguing against this.
Think about it, what does mantle material do when it reaches the earths surface? It cools into mafic and ultramafic rocks (for example, the oceanic crust).
And what do we see on mars? A northern hemisphrere dominated by an extensive low lying plain, and a negative gravity anomaly, EXACTLY analagous to an oceanic plain, but there's no mid ocean ridge.
And no, there is currently NO evidence to support Mars colliding with earth (and as I pointed out, recent evidence contradicts the massive impactor theory of lunar genesis).
The crust of the Earth is fairly thin, compared to its molten core, but that doesn't keep the crust from being of radically different thicknesses, ocean versus land.
As far as large moons go, ours is the exception, not the rule. Our moon is massive compared to the size of the Earth, whereas the moons of all the other planets are tiny in comparison (Pluto and Charon notwithstanding).
There is a viable argument to be made that Earth and Mars collided 4 billion years ago, leaving our moon for us and leaving a lot of debris that we call "the asteroid belt" just outside Mars' orbit.
Now whether this left behind something that sparked life on earth (or vice-versa) is anybody's guess.
Lichen can survive in space, and one of the Russian space station Mir's problems was that it had mold growing on its outside, in space.
No, I understood what you were saying, and I agree, and it would be relevant if we were talking about (for example) Cere's, however my contention is it's irrelevant, and my point remains the same - that the presence of the 'mound in the middle' is the result of fluid flow - whether it be plastic, or as a rubble pile, due to self gravitation, and doesn't preclude the possibility of the martian northern plains being caused by a massive impact.
The 'mound in the middle' is formed by the mantle material 'flowing back into place'.
I don't get why you're arguing against this.
Think about it, what does mantle material do when it reaches the earths surface? It cools into mafic and ultramafic rocks (for example, the oceanic crust).
And what do we see on mars? A northern hemisphrere dominated by an extensive low lying plain, and a negative gravity anomaly, EXACTLY analagous to an oceanic plain, but there's no mid ocean ridge.
And no, there is currently NO evidence to support Mars colliding with earth (and as I pointed out, recent evidence contradicts the massive impactor theory of lunar genesis).
QUOTE (Trippy+Jul 14 2008, 08:05 PM)
3) The massive impactor theory for the earths moon, as far as that goes, a recent article has cast some doubt on that theory, apparently some recent research suggests that although below the detection levels of previous experiments, the volatile content of the moons surface is too high to support that hypothesis.
I don't get the bit where an impact-formed Moon, at 4.5 billion years ago would negate the possibility of volcanic activity 3 billion years ago.
I don't get the bit where an impact-formed Moon, at 4.5 billion years ago would negate the possibility of volcanic activity 3 billion years ago.
QUOTE (N O M+Jul 15 2008, 08:36 PM)
I don't get the bit where an impact-formed Moon, at 4.5 billion years ago would negate the possibility of volcanic activity 3 billion years ago.
It's not about the volcanic activity (not as I understand it anyway).
One of the things that has always worked in in favour of the giant impactor theory is the fact that the samples were (as near as we could tell) completely dry.
This supported the giant impactor theory, because, well, when you think about it, slamming a mars sized object into a hot, young earth, vaporizing a bunch of crust, and ejecting it into the vacuum, you expect that sort of thing to be pretty dry, because there's a lot of heat energy involved in the impact.
However (it appears) the detection limit for previous experiments was around 50 ppm. It's my understanding that with the new experiments, they were expecting to find some water (say 5-10 ppm), because that's what the giant impactor model predicted, however, the recent experiments found 47 ppm of water, which for the giant impactor theory is a heck of a lot, possibly more then can be accounted for.
It's not about the volcanic activity (not as I understand it anyway).
One of the things that has always worked in in favour of the giant impactor theory is the fact that the samples were (as near as we could tell) completely dry.
This supported the giant impactor theory, because, well, when you think about it, slamming a mars sized object into a hot, young earth, vaporizing a bunch of crust, and ejecting it into the vacuum, you expect that sort of thing to be pretty dry, because there's a lot of heat energy involved in the impact.
However (it appears) the detection limit for previous experiments was around 50 ppm. It's my understanding that with the new experiments, they were expecting to find some water (say 5-10 ppm), because that's what the giant impactor model predicted, however, the recent experiments found 47 ppm of water, which for the giant impactor theory is a heck of a lot, possibly more then can be accounted for.
QUOTE
Think about it, what does mantle material do when it reaches the earths surface? It cools into mafic and ultramafic rocks (for example, the oceanic crust).
And what do we see on mars? A northern hemisphrere dominated by an extensive low lying plain, and a negative gravity anomaly, EXACTLY analagous to an oceanic plain, but there's no mid ocean ridge.
And no, there is currently NO evidence to support Mars colliding with earth
And what do we see on mars? A northern hemisphrere dominated by an extensive low lying plain, and a negative gravity anomaly, EXACTLY analagous to an oceanic plain, but there's no mid ocean ridge.
And no, there is currently NO evidence to support Mars colliding with earth
Other than everything you just wrote.
We've got thick continents and a thin ocean crust (and Hawaii smack in the middle of the Pacific) and vulcanism on the other side of the Earth (the mid-Atlantic ridge).
And they've got a gravitational anomaly, thick and thin crust, but no ocean.
Looks to me like Mars hit Earth, left us the moon close-in, and scattered debris which *might've* formed a moon for Mars if Mars had an ocean or some other tidal forces to exert on the asteroid belt to collect the farther-out debris into one solid object.
Heat makes steam, but steam cools even in space and returns to the body with the deepest gravitational well (that'd be Earth), where it makes weather which makes everything almost round and smooth.
Just my two cents, I'm not trying to get into a catfight over this.
QUOTE (wcelliott+Jul 15 2008, 02:58 PM)
if Mars had an ocean or some other tidal forces to exert on the asteroid belt to collect the farther-out debris into one solid object.
Our oceans are affected by tidal forces. But you don't need water for Tidal forces.
Even without water Earth would still be subject to tidal forces from the Moon.
Our oceans are affected by tidal forces. But you don't need water for Tidal forces.
Even without water Earth would still be subject to tidal forces from the Moon.
QUOTE (wcelliott+Jul 16 2008, 02:58 AM)
Other than everything you just wrote.
We've got thick continents and a thin ocean crust (and Hawaii smack in the middle of the Pacific) and vulcanism on the other side of the Earth (the mid-Atlantic ridge).
And they've got a gravitational anomaly, thick and thin crust, but no ocean.
Looks to me like Mars hit Earth, left us the moon close-in, and scattered debris which *might've* formed a moon for Mars if Mars had an ocean or some other tidal forces to exert on the asteroid belt to collect the farther-out debris into one solid object.
Heat makes steam, but steam cools even in space and returns to the body with the deepest gravitational well (that'd be Earth), where it makes weather which makes everything almost round and smooth.
Just my two cents, I'm not trying to get into a catfight over this.
Aside from the fact that there is no evidence of Mars ever having hit earth.
Look.
"Colliding with mars sized body"
Is not the same thing as "Colliding with mars"
Nothing I have said is evidence for Mars colliding with earth, in fact much of what I said is evidence against anything colliding with earth.
The early solar system was a very busy place, there were more, and bigger objects in the early solar system then there are now (or so theory predicts anyway).
From an astrophysical perspective, there's no evidence to suggest that Mars was ever anywhere near earth, there's nothing anomalous about its orbit, or rotational speeds, in fact the only thing potentially anomalous about mars is its size.
The pacific ocean is irrelevant, very little of it is older then 125 ma (in fact I believe the oldest it gets is 180ma) but the giant impactor theory predicts the impact occured 4 billion years ago.
Hawaii is irrelevant, Hawaii is a hotspot, they happen, there's some debate as to precisely how they happen, but they do happen. Hawaii is not the only hotspot in the world, the chain of islands and seamounts generated by this hotspot as the pacific plate drifts over it include the emperor seamounts, and extend all the way to the Kamchatka peninsula. the Hawaii hotspot is not special in any way, except perhaps its activity, but other hotspots include:
While it may be true that there is a theory that suggests that the 11 antipodal pairs of hotspots might have been caused by the impacts of large (>10km) bolides, the hotspot antipodal to Hawaii is is under lake victoria, and is not associated with the mid atlantic spreading ridge.
The mid atlantic ridge is irrelevant, it began fissuring in the Triassic (200-250 mya), which, once again is significantly younger then the impact thought to have caused the moon, and possibly older then the the hawaii hotspot. It should also be noted that the Amazon, Mississippi, and niger rivers are part of the complex that would form the mid atlantic ridge.
Again, the available evidence does not support your theory.
We've got thick continents and a thin ocean crust (and Hawaii smack in the middle of the Pacific) and vulcanism on the other side of the Earth (the mid-Atlantic ridge).
And they've got a gravitational anomaly, thick and thin crust, but no ocean.
Looks to me like Mars hit Earth, left us the moon close-in, and scattered debris which *might've* formed a moon for Mars if Mars had an ocean or some other tidal forces to exert on the asteroid belt to collect the farther-out debris into one solid object.
Heat makes steam, but steam cools even in space and returns to the body with the deepest gravitational well (that'd be Earth), where it makes weather which makes everything almost round and smooth.
Just my two cents, I'm not trying to get into a catfight over this.
Aside from the fact that there is no evidence of Mars ever having hit earth.
Look.
"Colliding with mars sized body"
Is not the same thing as "Colliding with mars"
Nothing I have said is evidence for Mars colliding with earth, in fact much of what I said is evidence against anything colliding with earth.
The early solar system was a very busy place, there were more, and bigger objects in the early solar system then there are now (or so theory predicts anyway).
From an astrophysical perspective, there's no evidence to suggest that Mars was ever anywhere near earth, there's nothing anomalous about its orbit, or rotational speeds, in fact the only thing potentially anomalous about mars is its size.
The pacific ocean is irrelevant, very little of it is older then 125 ma (in fact I believe the oldest it gets is 180ma) but the giant impactor theory predicts the impact occured 4 billion years ago.
Hawaii is irrelevant, Hawaii is a hotspot, they happen, there's some debate as to precisely how they happen, but they do happen. Hawaii is not the only hotspot in the world, the chain of islands and seamounts generated by this hotspot as the pacific plate drifts over it include the emperor seamounts, and extend all the way to the Kamchatka peninsula. the Hawaii hotspot is not special in any way, except perhaps its activity, but other hotspots include:
- Afar hotspot
- Amsterdam hotspot
- Anahim hotspot
- Ascension hotspot
- Azores hotspot
- Balleny hotspot
- Bermuda hotspot
- Bouvet hotspot
- Bowie hotspot
- Cameroon hotspot
- Canary hotspot
- Cape Verde hotspot
- Caroline hotspot
- Cobb hotspot
- Comoros hotspot
- Crozet hotspot
- Darfur hotspot
- Discovery hotspot
- East Australia hotspot
- Easter hotspot
- Eifel hotspot
- Fernando hotspot
- Galápagos hotspot
- Gough hotspot
- Guadalupe hotspot
- Hawaii hotspot
- Heard hotspot
- Hoggar hotspot
- Iceland hotspot
- Jan Mayen hotspot
- Juan Fernandez hotspot
- Kerguelen hotspot
- Lord Howe hotspot
- Louisville hotspot
- Macdonald hotspot
- Madeira hotspot
- Marion hotspot
- Marquesas hotspot
- Meteor hotspot
- New England hotspot
- Pitcairn hotspot
- Raton hotspot
- Réunion hotspot
- St. Helena hotspot
- St. Paul hotspot
- Samoa hotspot
- San Felix hotspot
- Shona hotspot
- Society hotspot (Tahiti hotspot)
- Socorro hotspot
- Tasmanid hotspot
- Tibesti hotspot
- Trindade hotspot
- Tristan hotspot
- Vema hotspot
- Yellowstone hotspot
While it may be true that there is a theory that suggests that the 11 antipodal pairs of hotspots might have been caused by the impacts of large (>10km) bolides, the hotspot antipodal to Hawaii is is under lake victoria, and is not associated with the mid atlantic spreading ridge.
The mid atlantic ridge is irrelevant, it began fissuring in the Triassic (200-250 mya), which, once again is significantly younger then the impact thought to have caused the moon, and possibly older then the the hawaii hotspot. It should also be noted that the Amazon, Mississippi, and niger rivers are part of the complex that would form the mid atlantic ridge.
Again, the available evidence does not support your theory.
Trippy. I hope you are right about the giant impact being unlikely. My reason for this is that the tides are probably one of the reasons there is complex life on Earth. If giant impacts are the only way a planet the size of ours can aquire a large moon, then I doubt many similar planets in other star systems would have one.
Nice deductive reasoning.
QUOTE (N O M+Jul 16 2008, 08:20 AM)
Trippy. I hope you are right about the giant impact being unlikely. My reason for this is that the tides are probably one of the reasons there is complex life on Earth. If giant impacts are the only way a planet the size of ours can aquire a large moon, then I doubt many similar planets in other star systems would have one.
Eh, I dunno, it's my understanding that yeah, you're right, the tides played an important role in the evolution of life on earth (or so the theory goes).
But, it's my understanding that observations suggest that such massive collisions were pretty common place in the early solar system (see some of the examples I listed in one of my earlier posts) for the reasons that I outlined in one of my other posts (that the solar system was a lot more crowded 4 billion years ago then it is now), observations also suggest that the early solar system wasn't significantly different from the comparably aged solar systems - there are stars with dust-disks that indicate comparably violent events (it's to do with infered particle size, and heat emissions, but I don't recall the all of the details).
Eh, I dunno, it's my understanding that yeah, you're right, the tides played an important role in the evolution of life on earth (or so the theory goes).
But, it's my understanding that observations suggest that such massive collisions were pretty common place in the early solar system (see some of the examples I listed in one of my earlier posts) for the reasons that I outlined in one of my other posts (that the solar system was a lot more crowded 4 billion years ago then it is now), observations also suggest that the early solar system wasn't significantly different from the comparably aged solar systems - there are stars with dust-disks that indicate comparably violent events (it's to do with infered particle size, and heat emissions, but I don't recall the all of the details).
But the common scenarios would be:
It would have to hit just right to get two bodies forming orbiting each other. Get the top-spin just right - the sort of thing that usually takes several cold ones to manage.
- splat - results in one slightly larger planet
- boom - little pieces flying everywhere
- bounce - billiards. Probably only likely with a glancing blow.
It would have to hit just right to get two bodies forming orbiting each other. Get the top-spin just right - the sort of thing that usually takes several cold ones to manage.
QUOTE (N O M+Jul 16 2008, 03:22 PM)
But the common scenarios would be:
Actually, it's my understanding that the collision that was supposed to have resulted in the moon was a 'glancing blow', and statistically, this is probably by far the most probable outcome when dealing with two bodies of comparable diamaters (small bolides can be effectively treated as point objects when considering hit/miss scenarios).
- splat - results in one slightly larger planet
- boom - little pieces flying everywhere
- bounce - billiards. Probably only likely with a glancing blow.
Actually, it's my understanding that the collision that was supposed to have resulted in the moon was a 'glancing blow', and statistically, this is probably by far the most probable outcome when dealing with two bodies of comparable diamaters (small bolides can be effectively treated as point objects when considering hit/miss scenarios).
I was never any good a playing Asteroids
But a certain episode of Red Dwarf comes to mind
But a certain episode of Red Dwarf comes to mind
QUOTE (N O M+Jul 16 2008, 09:04 PM)
I was never any good a playing Asteroids
But a certain episode of Red Dwarf comes to mind
Black hole in the corner pocket.
Didn't Danger Mouse do something similar?
But a certain episode of Red Dwarf comes to mind
Black hole in the corner pocket.
Didn't Danger Mouse do something similar?
As much as I love rules of thumb and back-of-the-envelope calculations, when the topic is orbital mechanics or three-body collisions or fluid dynamics, I tend to remain silent and let the guys with the supercomputers do their thing and just hope they got their code written correctly.
Unfortunately for us, the problem of how we ended up with a moon involves all three of those things you need supercomputers to model.
And yes, I agree that a glancing blow is most likely between two objects of comparable sizes. (I prefer short-combo-shots to long-straight-shots in pool, myself.)
Unfortunately for us, the problem of how we ended up with a moon involves all three of those things you need supercomputers to model.
And yes, I agree that a glancing blow is most likely between two objects of comparable sizes. (I prefer short-combo-shots to long-straight-shots in pool, myself.)
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