reply to post by atlasastro
www.lpi.usra.edu... is that affiliated with NASA?
Can you give me the odds of an object the size of our Craft..err Moon ... finding itself 'captured' by our planet - over say our Suns pull?
I'm pretty uneducated, as you can tell - never passed an exam to get into the field of Astronomy...
So you could also say us Earth dwellers know all about the Craft...err Moon (sorry - dunno why I keep doing that!) and that's that? Or would you say
there are still a few oddities that can't be explained on our Craft ...Moon (old habits you know) such as "classified" things and the such - I mean
you sound like you know it all - I am all for learning something *new*
Taken from George H. Leonard - Somebody Else Is On The Moon, 1976.
"Isaac Asmoviv says there are nine moons in our solar system that have been captured: one of Neptune, one of saturn, and seven of Jupiter. He bases
this on what he calls the "tug-of-war" ratio: the attraction of the planet verses the attraction of the sun. This ratio ranges from Miranda, a
satellite of Uranus, which has a tug-of-war ratio of 24,600, to the seventh moon of Jupiter, which has a ratio of 1.03. He calls the other satellites
"true satellites."
And then he comes to our Moon. It is important to quote him:
It is a shame that one small thing remains unaccounted for; one trifling thing I have ignored so far, but - WHAT IN BLAZES IS OUR MOON DOING WAY OUT
THERE? It's too far out to be a true satellite of Earth, if we go by my beautiful chain of reasoning - which is too beautiful for me to abandon.
It's too big to have been captured by the Earth. The chances of such a capture having been effected and the Moon then having taken up a nearly
circular orbit about the Earth are too small to make such an eventuality credible.
There are theories, of course, to the effect that the Moon was once much closer to the Earth (within my permitted limits for a true satellite) and
then gradually moved away as a result of tidal action. Well, I have an objection to that. If the moon were a true satellite that originally had
circled the Earth at a distance of, say, 20,000 miles, it would almost certainly be orbiting in the plane of Earth's equator and it isn't.
But, then, if the Moon is neither a true satellite of the Earth nor a captured one, what is it?...
he goes on to conclude the tug-of-war ratio for the Moon: 0.46. We would lose the tug of war with the sun. We - Earth - attract the Moon half as
strongly as does the Sun.
*Isaac Asmoviv, Asmoviv On Astronomy, Mercury Press, Inc, 1963."
[edit on 28-6-2009 by watchZEITGEISTnow]