Mars' Reull Vallis: a River Ran Through It

Press2ToContinue sends this quote from a European Space Agency news release: "ESA's Mars Express imaged the striking upper part of the Reull Vallis region of Mars with its high-resolution stereo camera last year. Reull Vallis, the river-like structure in these images, is believed to have formed when running water flowed in the distant martian past, cutting a steep-sided channel through the Promethei Terra Highlands before running on towards the floor of the vast Hellas basin. This sinuous structure, which stretches for almost 1500 km across the martian landscape, is flanked by numerous tributaries, one of which can be clearly seen cutting in to the main valley towards the upper (north) side."

Almost Certainly Life At Least At 1 Point In Time

[gpronger]

It would seem that the more we understand Mars, the much greater likelihood that at minimum primitive (single cell) life would have evolved. Given life here on Earth started within a billion years of creation, the similarities between the two, would seem to have been near identical. Initially, both would have had similar atmospheres, and formation of liquid water. It was very close here on Earth that life then developed.

Re:Almost Certainly Life At Least At 1 Point In Ti

[Teancum]

Given even the relatively recent exchanges of material between Mars and the Earth, much less similar incidents in the past (including an asteroid impact that destroyed 99.9% of all species here on the Earth) I think it is very likely that the genuine origin of life, especially simple things like blue-green algae, may have even originated on Mars or at least it would be hard to declare where it happened. This only has to happen once every hundred million years or so to still be significant, and the K-T event (something capable of ejecting a piece of swamp and sending that to Mars) happened only 65 million years ago.

If MER or some future space probe discovers actual life on Mars, I'm willing to suggest that the DNA would even be very similar to what is found here on the Earth and through DNA analysis you may even be able to find a common ancestor between that life and stuff found here on the Earth. It certainly couldn't be ruled out.