This is John Batchster, conversation with my good colleague Bob Zimmerman.

NASA is looking for signs of former organic life on Mars.

And they're looking in an unusual place, Earth, for conditions that are similar to that on Mars.

Bob explains here, we're not ruling out life in the past, certainly,

not even ruling life out right now. However, there's lots of caveats. The search for microbiology,

even extreme microbiology on Mars.

More of this later tonight.

Well, there was a research team here on the ground at NASA's Guided Space Flight Center

that wanted to find out if microbiology could survive on Mars for very, very long times. This doesn't mean it's alive,

let's say the remnants, the corpses of microbiology. How long could it survive? So they did a simulated

test on the ground here, simulating both sediment on Mars as well as ice on Mars, and they put in it microbiology, and they

exposed it into radiation that was simulating a 50 million year time span.

And this was an E. coli sample.

And what they found was that in the sediment, it decayed very quickly and fell apart.

While in the ice, the pure water ice, the ecoli sample survived the 50-minute time sample.

It might have been degraded.

It might have been not alive, but the sample itself survived.

So what this research suggests is that if you want to look for ancient microbiology on Mars,

you can't go to the equatorial regions, the dry tropics of Mars, where there is no near surface ice.

You've got to go above 30 degrees latitude to where

there's lots of ice near the surface on Mars to the northern or southern latitudes. Ironically,

we've been sending both all our rovers to the dry tropics pretty much. Preservation and curiosity,

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