Too much to respond to at once. I seem to have stirred up a hornet's nest. (It's a good feeling, and about time somebody did it)
The problem is when we feel so fervertly towards such a thing as life on Mars, we tend to take huge leaps of faith.
"What about life underground on Mars? How do we know that microbial life does not exist underground? How can we rule out this possibility?"
Well, we haven't ruled out any possibility. I didn't say that it was impossible, just highly unlikely. I said that the most logical conclusion based on evidence so far, is that there is no extant life on Mars. (Ok and no past life either). Why? Because to say otherwise would require evidence. There is no evidence.
As a counter argument, and trying to remain totally impartial in the argument. (Try saying this aloud - It's very therapeutic)
"What about the possibility that there are no suitable underground habitats for life? How can we rule out this possibility?"
What do we really know about underground conditions on Mars - temperatures, the presence of water etc? We don't include guesses, intelligent or otherwise. Do underground heat sources exist? Based on what? To what extent?
Superoxide is generated continuously on the surface of Mars based on simulated atmospheric conditions, with iron oxide mixes similar to those on Mars. Now the brine question - For the (what is it?) 1.6 hours per day, 60 sols per year that water is stable from an equilibrium point of view, if that water is actually present on the surface during any of that time, then it will tend to react with the superoxide to form hydrogen peroxide, another oxidizing agent.
As an analogy, let's take ether (say diethyl ether) on Earth. What happens if we pour it on the ground. Well it's a volatile solvent, and it will evaporate very quickly. Why does it evaporate? It should be liquid under most conditions on earth. It's below its boiling point, and theoretically it can exist in liquid form.
The same goes for Mars. At the low pressure of the Martian atmosphere, even in the narrow temperature range in which water can exist, it will tend to subliminate. Any free water or brine will evaporate, and absorb heat from the surrounding soil. (Ever hear about evaporative air conditioning?) The soil is generally about 60 degrees warmer than the atmosphere, so it makes sense that heat would be drawn from the soil. Any water would then produce its own microclimate which is cooler than the surrounding area. It will either freeze and evaporate, or evaporate totally.
Ok, what about Levin? Doesn't he talk about a limitation in evaporation due to the near saturation of the Martian atmosphere?
What do you think would happen to the Martian atmosphere during a regime where water is evaporating rapidly? Would it be (cool man) she's slowly buildin' up these nice calm theoretical layers that would prevent evaporation?
Well one obvious sign of extensive evaporation would be a thermal anomaly, another obvious sign would be extremely windy atmospheric conditions.
Windy conditions and equilibrium conditions do not compute.
What about all this ice in the Equatorial regions? Well all we know is that there is hydrogen. We have found some very stable hydrated minerals at both Gusev and Meridiani. Could this be your "Equatorial Ice" ?
Sorry to upset your reverie here. I'll concentrate on the other thread in the Open Forum.