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View Full Version : Did Venus have a Moon?



tofu
2004-Mar-22, 03:36 PM
Are there any theories that suggest that Venus may have undergone a large primordial impact similar to the impact Earth suffered that resulted in the creation of our Moon? I wonder if there is any even remote possibility that Mercury could be the other half of that impact.

2004-Mar-22, 05:52 PM
Are there any theories that suggest that Venus may have undergone a large primordial impact similar to the impact Earth suffered that resulted in the creation of our Moon? I wonder if there is any even remote possibility that Mercury could be the other half of that impact.

Some have speculated that the Cytherian retrograde rotation may be due to an impact. I think it is unlikely that Mercury was the result.

ToSeek
2004-Mar-22, 06:06 PM
That's astronomer Tom Van Flandern (http://www.metaresearch.org/home.asp)'s claim (that Mercury is a former moon of Venus), but he also thinks that Mars is the former moon of a planet that exploded, that planets emerge from their stars by fission and in pairs, that gravity travels at infinite speed, and that the Face on Mars was created by an alien civilization.

tofu
2004-Mar-22, 06:16 PM
lol ToSeek. OK So I guess I should just drop it. But, given Venus' retrograde rotation it's clear that it was subject to a large impact. It could be that the two proto-planet's merged to form present day Venus. Or maybe the resulting material didn't remain in orbit to form a moon and instead ended up on the surfaces of other planets or as asteroids throughout the solar system.

aurora
2004-Mar-22, 08:35 PM
lol ToSeek. OK So I guess I should just drop it. But, given Venus' retrograde rotation it's clear that it was subject to a large impact. It could be that the two proto-planet's merged to form present day Venus. Or maybe the resulting material didn't remain in orbit to form a moon and instead ended up on the surfaces of other planets or as asteroids throughout the solar system.

I did see a paper awhile back that modeled Venus, and determined that regardless of what it's original rotational speed, it would always end up in one of two configurations. One of which is the rotation that it currently has. So I don't think it is a given that there was a major collision.

I do not remember which journal had the paper, I probably read a summary of it in one of the monthlys (Mercury perhaps, or S&T) last fall.