‘Dandruff’ could contaminate Phoenix landing site

[LARRY KLAES]

‘Dandruff’ could contaminate Phoenix landing site

Published online 6 June 2008 | Nature | doi:10.1038/news.2008.878

Dead microbes and skin flakes from Earthlings may scupper the
search for organic molecules.

Eric Hand

The most detailed photo ever of martian dust - but Phoenix may
have less success in finding organic molecules.NASA/JPL-Caltech/
Univ. Arizona

Could Phoenix’s search for organic molecules on Mars be foiled
by dandruff from Earth? After a successful landing last month on
the planet’s northern plains, the NASA spacecraft is busily scraping
through the martian dirt. Next week, the mission team plans to
use one of its premier instruments, the Thermal and Evolved Gas
Analyzer (TEGA), to test its first baked soil sample for molecules
containing carbon.

The search for the organic building blocks of life has been a
major selling point for Phoenix; many press accounts have
eagerly, yet mistakenly, foreshortened the mission’s raison
d’etre to ‘the search for life’. Yet some mission scientists say
that it is the science goal least likely to succeed, partly because
TEGA is so sensitive that it may end up sensing only contamination
from Earth.

“We will see organics, for sure, because we’re bringing them,”
says Aaron Zent, a mission scientist from NASA’s Ames Research
Center in California. Likely contaminants include skin flakes,
dead microbes and volatile lubricants. “The problem with an
instrument so sensitive is all you detect is your own schmutz,”
says Zent.

Full article here:

http://www.nature.com/news/2008/080606/full/news.2008.878.html