I've been trying to quote Bowyn Aerrow directly but the system isn't allowing me to do so. For some unknown reason, rather than quoting his post it fills the posting field with a saved draft from a previous visit to this thread. Not sure how to work around that. Anyway:
Bowyn Aerrow Wrote:Mars has the clear evidence of water activity, plenty of erosion and even dried dead sea basins.
Actually, at this point, that is highly debatable. Even though mars is 1/2 the diameter of earth, it has mountains that dwarf ours by magnitudes and the Valles Marineris (among many anomalies) is 1o times longer and 5 times deeper than the Grand Canyon. We don't know what caused these tremendous anomalies but water erosion is clearly not the answer.
One interesting hypothesis is solar electrical discharge. This hour 24 minute video goes into it in detail but the 'gist' of the idea can be gotten in the first 10 to 15 minutes. The images alone are worth the attention. Mars is a truly unusual world: