Originally posted by pavilThe problem I have with this explanation is in the comparison with the plant Venus. Venus has no magnetic field yet its atmosphere is over 90 times that of Earth's. I believe that our understanding of the nature of these planetary environments is lacking to say the least.
Originally posted by BalderAsir
so the question is, where'd it all go? How does a planet go from having running water, long enough to cause erosion to nothing?
Same as it's atmosphere.... ripped away bit by bit by the solar wind due to lack of a real magnetic field.
Having said that I feel BalderAsir's question is valid. What happened to the planets Mars and Venus and when did these events occur?
edit on 9/28/2012 by Devino because: (no reason given)