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ToSeek
2006-Oct-23, 10:26 PM
Viking landers may have missed Martian life (http://www.newscientistspace.com/article.ns?id=dn10361&feedId=online-news_rss20)


NASA’s twin Viking spacecraft may have missed signs of life during their examination of the Martian surface 30 years ago. Researchers now say that the landers’ experiments were not sensitive enough to find life and in any case may not have been able to spot the strange forms that Martian life might take.

The results from Vikings’ onboard experiments are confusing because some tests suggested the presence of organisms capable of digesting organic molecules. But heating the soil with a gas-chromatograph mass spectrometer (GCMS) to release these organic molecules found nothing, causing most scientists to rule out life. Instead they put the soil reactivity down to the presence of peroxides or other reactive substances.

Now, a paper by Rafael Navarro-Gonzalez of the University of Mexico and others demonstrates that the GCMS instrument was incapable of detecting organic compounds even in Mars-like soils from various locations on Earth. This includes Chile's Atacama desert, where other tests prove that living microbes are indeed present.

In some soils – including samples taken from Rio Tinto in Spain, which contain iron compounds similar to those detected in Mars soils by NASA's rover Opportunity, the sensitivity of the GCMS was actually a million times lower than its claimed threshold for detection.

PhantomWolf
2006-Oct-27, 03:20 AM
One way to rule of life is to add distereoisometric sugars to it. Life will react to only one of them, chemical reactions to both.

Cugel
2006-Oct-27, 10:35 PM
One way to rule of life is to add distereoisometric sugars to it. Life will react to only one of them, chemical reactions to both.

But will every life form react to di...sugar in the first place?
For instance, would methanogens that eat hydrogen be fond of sugar?
Or the 'nuclear' critters described in this article: http://www.marsdaily.com/reports/Study_Fuels_Debate_Of_Life_On_Mars_999.html

And even if they do, can you be sure that every conceivable life form will actually consume sugar? I don't know, but I doubt it.

01101001
2007-Jan-08, 07:14 AM
Viking landers may have missed Martian life (http://www.newscientistspace.com/article.ns?id=dn10361&feedId=online-news_rss20)

Missed it? They killed it!

CNN: Scientist: NASA found life on Mars - and killed it (http://www.cnn.com/2007/TECH/01/07/mars.life.ap/)


Two NASA space probes that visited Mars 30 years ago may have found alien microbes on the Red Planet and inadvertently killed them, a scientist is theorizing.

The Viking space probes of 1976-77 were looking for the wrong kind of life, so they didn't recognize it, a geology professor at Washington State University said.

Dirk Schulze-Makuch presented his theory in a paper delivered at a meeting of the American Astronomical Society in Seattle, Washington.

novaderrik
2007-Jan-08, 07:24 AM
haven't people been saying this for the last 30 years or so?

djellison
2007-Jan-08, 08:31 AM
"looking for the wrong kind of life, so they didn't recognize it"

That's just so wrong. They were looking for X and didn't find X. That doesn't dictate that Y exists and they failed to find it. We didn't know what to go and look for, for a first try, for instruments designed at the beginning of the 1970's - it was a good effort.

Doug

Grand_Lunar
2007-Jan-09, 01:38 AM
Missed it? They killed it!

CNN: Scientist: NASA found life on Mars - and killed it (http://www.cnn.com/2007/TECH/01/07/mars.life.ap/)

Oops!

Guess this means we inadvertantly started our own version of "The War of the Worlds".

mugaliens
2007-Jan-09, 06:52 PM
Given the meteors which have impacted our planet, including the Yucatan nicety, I've little doubt that live escaped Earth and made it Mars and other planets intact. Whether that life adapted there is a question which has yet to be answered.

The reverse could be true - Earth life might have come from another planet, or possibly, even a nearby star system.