Martian Chemistry Find: Bad for Life?

August 04, 2008

If you didn't catch my previous post about the Mars-potential-for-life rumors, click here.

In short, quite a few  people ran stories describing a positive habitability-of-life result for Martian soil. Those reports stemmed from from a recent wet chemistry test by none other than the Phoenix Mars Lander, but were distorted in "retelling on the Internet," as Phoenix scientist Michael Hecht told me.

Now NASA has just put out a new press release, and -- oops -- looks like that "great for life" result might in reality be the opposite.

Scientists found perchlorate, which is an oxidizer, a DNA-munching chemical, and something that's not pleasant for supporting life.

The press release beat around the bush quite a bit about concluding it's a bad sign, but one interesting note was this (emphasis added):

The team also is working to totally exonerate any possibility of the perchlorate readings being influenced by terrestrial sources which may have migrated from the spacecraft, either into samples or into the instrumentation.

Translation: Rocket fuel Solid rocket propellant -- which perchlorate is an oxidizer for -- could have contaminated Phoenix somehow. Thing is, Phoenix used liquid hydrazine fuel to land and not solid rockets to land on the Martian surface. (Thanks to Sara Hammond for the correction!)

The Phoenix team, however, thought digging deep to get to pure samples would prevent any contamination. That might not be the case, though.

So, the final word? Still uncertain, but it's not a good thing any way you look at it. Either:
a) Pure Martian soil samples may be far more difficult to obtain than thought or...
b) Perchlorate is a major component of Martian soil (possible ouch for microbes).

We'll have to wait until tomorrow after 1 p.m. EDT, when NASA holds a press conference, to get more information.

My hope, having written an article for SPACE.com last year on the subject, is that it's fuel contamination. Even though Phoenix didn't use solid rockets to land. But it's just that: A hope.

Photo: NASA/JPL/Univ. of Arizona/Univ. of Michigan