User:Robertinventor/Simple animals could live in Martian brines - Extended Interview with planetary scientist Vlada Stamenković: Difference between revisions

'''''(background information):''''' Stamenković et al incite theira paper cite research from 2014 that showed that some simple sponges can survive with only 0.002 {{w|Mole (unit)|moles}}per cubic meter (0.064 mg per liter) <!-- first page of Nature paper, "Meanwhile, whereas aerobic microbial life and simple animals need O₂ dissolved in liquids in sufficiently large concentrations to survive, recent experiments, observations and calculations have lowered the required limits of concentrations of dissolved O₂ for aerobic respiration to ~10−6 mol m−3 in microorganisms and to ~2 × 10−3 mol m−3 in sponges"-->. Some microbes that need oxygen can survive with as little as a millionth of a mole per cubic meter (0.000032 mg, or 32 nanograms per liter). In their model, they found that there can be enough oxygen for microbes throughout Mars, and enough for simple sponges in oases near the poles.

Stamenković et al found that even in the worst case they could devise, oxygen levels throughout Mars would be enough for the least demanding {{w|Aerobic organism|aerobic}} (oxygen using) microbes, at around 2.5 millionths of a mole per cubic meter (0.0008 mg per liter). That's the value for the tropical southern uplands, where temperatures are high and the atmosphere is thin, and for their brine with the lowest oxygen solubilities, sodium perchlorate. They also calculated this figure using their worst case estimate (where they do the calculations on their least optimistic assumptions). However, they give reasons for believing that their more optimistic best case calculations are close to the true situation.