Was there water on Mars long enough for the origination of life?

Blob · #1 (**permalink**) 19-October-2006, 07:49 PM

Quote:

Based on the lovely green rock, olivine, also known as the gemstone, peridot, a Virginia Tech graduate student has created a mineral lifetime diagram that provides the a clue to when and for how long there might have been water on Mars.
Amanda Albright Olsen of Altoona, Pa., a doctoral student in geosciences at Virginia Tech, will present the research at the Geological Society of America national meeting in Philadelphia on Oct. 22-25. Virginia Tech Geosciences Professor Donald Rimstidt of Christiansburg, Va., is co-author.
Olivine, a silicate mineral rich in magnesium and iron, is found on earth in volcanic rock (basalts). It has also been spotted on Mars – most recently and in significant amounts by NASA's Mars Odyssey spacecraft (Geology, June 2005). Because life requires liquid water and because olivine dissolves in water, Olsen set out to establish how long it takes olivine to dissolve. The answer could help scientists determine if there was liquid water on Mars long enough for life to develop.

Ronald Brak · #2 (**permalink**) 21-October-2006, 03:37 PM

It's interstesting, but I think it's possible that warm seas weren't required for life to appear on earth. It may well have developed underground. But since we don't know, I'd still say the longer seas lasted on mars the better the chances of life. I also think that if there was life on mars once, there is life now, because it's darn hard to get rid off. (Ask a nurse or lab tech who has to sterilize stuff.)

JonClarke · #3 (**permalink**) 22-October-2006, 12:28 AM

Lot's of problems with that article, as indeed there all in all articles what try to constrain the prevelence of liquid water on Mars by the olivine distribution.

Olivine does not dissolve in water, to alters to other minerals. Alteration rates are strongly determined by factors additional to pH - salinity, Eh, volume of water transmissivity,and temperature. Furthermore olivine is being produced through Martian history by volcanic eruptions.

We find olivine in river and coastal sediments on Earth today, also on exposed rock surfaces. Does this mean that this imposes constraints on the history of water on Earth? Of course not.

Jon

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode