NASA's next small step may be into Martian manure

HAVE they found poo on the Red Planet?

Space websites around the world are abuzz with speculation about what NASA's latest Mars probe may have found.

The excitement has been triggered by a report in the journal Aviation Week that the space agency alerted the White House to "major new Phoenix lander discoveries concerning the 'potential for life' ".

Jon Clarke, a geologist with Mars Society Australia, a group dedicated to Martian exploration, said the report had triggered a frenzy of interest. "Chat groups are all speculating about what it is," Dr Clarke said. "We have had emails flying backwards and forwards. Something is certainly in the breeze."

The magazine reports that the discovery was made by a Phoenix experiment package called the Microscopy, Electrochemistry and Conductivity Analyser, or MECA, which is designed to mix Martian soil with water brought from Earth.

In June NASA revealed the instrument had found Martian soil was not toxic, as had been thought, and could be used to grow crops such as asparagus.

Asked to speculate yesterday on what it may have now found, Dr Clarke said the instrument was designed, among other things, to spot dissolved ammonium and nitrate salts.

"On Earth, if you have a lot of ammonium and nitrate it usually means there is organic activity. We excrete it as waste and other organisms use it."

High volumes of such chemistry in a river could point to effluent run-off from a farm. While not life itself, "it could be a sign of biology. Ammonium nitrate is a fertiliser and if present might indicate greater habitability," Dr Clarke said.

NASA has said little about the claims, although it has used the social networking site Twitter to downplay the reports.

The Twitter site, where the Phoenix team has been posting text messages, says: "Heard about the recent news reports implying I may have found Martian life. Those reports are incorrect."

A later message adds: "Reports claiming there was a White House briefing are also untrue and incorrect."

But the magazine did not say it was life that had been discovered but evidence relating to the planet's "habitability".

Aviation Week strongly hinted that an announcement, which it said could be made next month, would be far more dramatic than last week's news that Phoenix had confirmed there is water ice on the planet.

Dr Clarke said the predicted announcement "obviously … has to be bigger than the asparagus [announcement]". But it "could all be a storm in a tea cup". Just in case, "our ears are perked. We can't wait."