It’s been a busy few days for the Phoenix Mars lander rumour-mill. On Friday, an article was published in Aviation Week reporting an undisclosed source from the NASA team analysing results from the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) had come forward saying Phoenix scientists were in communication with the White House. Apparently there had been new, “provocative” results to come from the MECA, possibly a bigger discovery than last Thursday’s announcement about the scientific proof of water in the Martian regolith. Naturally, the blogosphere went crazy in response to this news. Yesterday, the Phoenix team issued a press release focussing on conflicting results from the MECA and Thermal and Evolved-Gas Analyzer (TEGA) instruments. A MECA sample was found to contain a toxic substance known as perchlorate, usually an oxidizing by-product from industrial processes here on Earth. However, a recently analysed sample from the TEGA turned up no supporting evidence for perchlorate. The study is ongoing. Today, the Phoenix team organized a press conference to discuss a more positive view on the possible discovery of perchlorate, and fired back at recent allegations that science was being withheld from the public…
The Phoenix mission has had an outstanding record of transparency and communicating its science into the public domain. So, one can understand the frustration mission scientists felt when “outrageous” stories (according to Peter Smith, Phoenix principal investigator) were circulated by Aviation Week alleging secrecy about Phoenix findings, strongly indicating that something huge had been discovered and the White House had to be notified. “We want to set the record straight…we’re not with-holding anything” NASA spokesman Dwayne Brown declared at the special press briefing today. The Phoenix team went on to say that the sketchy details in the Aviation Week article led to the huge amount of “speculation” that was thrown around in follow-up stories.
Indeed, there was a significant finding in the works, but the scientists needed more time to analyse the results before issuing a press release on finding perchlorate in the MECA sample. Although the Aviation Week article did specifically say Phoenix was not capable of discovering life, it didn’t stop a number of reports indicating that life had been discovered on the Red Planet (hence the need to communicate the discovery with the President’s Science Advisor first). These speculative claims reached fever-pitch, prompting Phoenix’s Twitter feed to state “Heard about the recent news reports implying I may have found Martian life. Those reports are incorrect.” The speed at which these rumours spread was startling and probably took NASA completely off-guard. This is probably why the perchlorate discovery was announced before a complete and rigorous study could be carried out.
So is perchlorate the death-nail for the possibility of finding suitable conditions for life to be seeded? According to Phoenix scientists, oxidizing chemicals are not always ‘bad news’ for life. “It does not preclude life on Mars. In fact it is a potential energy source,” said William Boynton of the University of Arizona. Indeed, perchlorates have been found in Chile’s highly arid Atacama Desert, a location often used as an analogue for the Martian landscape. Organics in nitrate deposits associated with perchlorates have been found in these harsh conditions, possibly indicating life may form in similar circumstances on Mars.
Although the Phoenix scientists are fairly upbeat about this new finding, other scientists not associated with the mission are cautious. At first glance, perchlorate “is a reactive compound. It’s not usually considered an ingredient for life,” said Brown University geologist John Mustard. Regardless, we will have to wait until all the results are in, especially from the follow-up TEGA sample. Jumping to conclusions are obviously not very helpful to the Phoenix team currently trying to decipher what they are seeing from experiments being carried out by a robot, 400 million miles away.