Andean Bioexpedition To Highest Lake Mimics Old Mars

An anonymous reader writes "The analogy between the highest lake on Earth and extremes on Mars has NASA Ames and the SETI Institute collaborating to analyze microbial samples. The combination of high ultraviolet radiation, low oxygen, low atmospheric pressure approximates the closest one can come to what Mars was like 3.5 billion years ago when it was wet and warm. The expedition page has a running schedule for the next 3 weeks."

Comments

Re:3.5 million years ago ?

[f97tosc]

Sure, our knowledge of Mars 3.5 billion years ago is probably pretty sketchy. However, we don't have to know that much to figure out which parts of today's Earth are the best approximation. I think we can be pretty confident that a very high altitude (dry, cold, thinner atmosphere) is better than a very low one (moist, warm, thick atmosphere).

Tor

Re:HR is forgotten

[raduga]

The theories are, that Mars was warmer as a confluence of several things, essentially coming back to the internal heat.

Sources:

• Heat leftover from kinetic energy of small planetismals colliding to form Mars-as-we-know-it
  This radiates slowly over time, by Newton's law
• Heat from radioactive decay of Uranium and other superheavy metals
  rate of decay diminishes according to the half-life of the nuclides

Cascade effects:

• Much hot material in core keeps core material in liquid phase.
  
• Rotating fluid core creates magnetic field, which interacts with solar wind, to keep charged particles from eroding the atmosphere (particularly Water, from dissociation)
• Denser atmosphere supports greenhouse warming; increased atmospheric H2O supports greenhouse strongly

Current thinking is that Mars was enough smaller than Earth that it accumulated less of the critical radioisotopes needed to maintain an active interior for a long time.