• More Blogs
• Observations »
• Bering in Mind »
• Cross-check »
• Extinction Countdown »
• Solar at Home »
• Expeditions »
• Guest Blog »
• Anecdotes from the Archive »

Martian soil may be less Earthlike and less hospitable to life than researchers believed.

NASA's Phoenix Mars Lander has found traces of perchlorate in two soil samples analyzed during the past month, the space agency announced today. The results appeared to be the same ones rumored this weekend by AviationWeek.com to have been seen by the White House and to reflect Mars's habitability for life.

Perchlorate, or ClO4, is a naturally occurring and man-made chemical that is the primary ingredient in solid rocket fuel, according to the EPA. Where such a contaminant might have come from is unclear. The fuel in the thrusters that Phoenix used to land on Mars was made of hydrazine, not perchlorate.

The presence of such a chemically reactive compound in Martian soil would seem to make that soil less supportive of life. Here on Earth, high doses of perchlorate can interfere with thyroid hormone production, which can harm babies in the womb.

Phoenix's MECA wet chemistry experiment detected the chemical. NASA said the Phoenix team was waiting for the craft's gas analyzer, TEGA, to confirm the finding. The agency said that results from a TEGA experiment on Sunday, which analyzed a sample take from directly above the soil's ice layer, did not detect perchlorate.

"This is surprising since an earlier TEGA measurement of surface materials was consistent with but not conclusive of the presence of perchlorate," Peter Smith, Phoenix's principal investigator at the University of Arizona, Tucson, said in the NASA statement.

NASA said the team is also working to confirm that the chemical was not a stow-away from Earth that crept into the instruments or the samples. The agency said it would provide further information tomorrow afternoon.

13 Comments

1. 1. Mr Anderson 07:52 PM 8/4/08

   They say perchlorate comes from the exhaust of rocket engines. Maybe It someones old landing site.

   Reply | Report Abuse | Link to this

2. 2. Mr Anderson 07:54 PM 8/4/08

   They say perchlorate comes from the exhaust of rocket engines. Maybe Its someone or somethings old landing site. Think about It.
   
   Mr Anderson

   Reply | Report Abuse | Link to this

3. 3. ruffyy 07:58 PM 8/4/08

   Maybe we weren't the first ones there!

   Reply | Report Abuse | Link to this

4. 4. mikecimerian 08:16 PM 8/4/08

   Nice to know such a powerful oxidizer is present on Mars. That much "kicking power" wouldn't have to get shuttled there. A chemically Inert Mars would be worse news.

   Reply | Report Abuse | Link to this

5. 5. Peckerwood 10:53 PM 8/4/08

   Now, does that mean that we could use the perchlorate in Martian soil to produce rocket fuel? If so, could that be used to our advantage, perhaps by manufacturing fuel on Mars for other, further out journeys or the return voyage home? Or could the possible abundance of perchlorate be useful in other ways? Perhaps to somehow be used as a power source on Mars? How does perchlorate figure in the manufacture of rocket fuel? If it truly is the "primary ingredient" of rocket fuel then clearly it may have some energetic potential. If so, that could help justify more extended missions to Mars, perhaps even the construction of human habitations. I mean, if it was coal and not perchlorate then, regardless of the environmental consequences, I suspect THAT would excite some interest... or am I just too stupid to understand this stuff? If Mars can't really support life in its natural environment then that would relieve us of any concern over what our toxic emissions could do to the environment. We could live in sealed "biodome" type structures and befoul the environment with perchlorate emissions all we want to. I'd like to take this time to publicly stake the first claim to a perchlorate mine on the planet Mars. There's gotta be some sort of profit there, that's all I'm saying.

   Reply | Report Abuse | Link to this

6. 6. targetpractice.v01 01:08 AM 8/5/08

   Perchlorate certainly is harmful to Earth-life, but does it really discourage the idea of life on Mars?
   Consider that any life which developed independently on Mars might have a completely different metabolism from Earth-life. On Earth, photosynthetic lifeforms produce the highly oxidizing gas O2. Who's to say an alien metabolism wouldn't produce ClO4 in a comparable process?
   
   What's really interesting is that there are several species of bacteria on Earth that can use perchlorate as an oxidizer in place of O2 (The journal Nature offers a nice overview, if you happen to have a subscription or be on a college campus: www.nature.com/nrmicro/journal/v2/n7/execsumm/nrmicro926.html). If perchlorate does turn out to be abundant on Mars, then it seems to me there's a real possibility for the existence of past or present complex microorganisms in the soil.

   Reply | Report Abuse | Link to this

7. 7. cyberbian 01:32 AM 8/5/08

   Perchlorate is harmful to the human thyroids ability to absorb iodine.
   
   Not exactly harmful to all life forms is that?
   
   Reporting seems to recycle the first idiot response to come along infinately. As long as the idiot response backs the no life hypothesis. Curious isn't it?

   Reply | Report Abuse | Link to this

8. 8. zendog 07:45 AM 8/5/08

   Is it just coincidental that the Atacama Desert where naturally formed perchlorate is found has also used by NASA as a local test-site alternative to Mars? Could the detection of perchlorate be an anomaly resulting from contamination of the Lander by soil from Atacama?

   Reply | Report Abuse | Link to this

9. 9. kruzzah 06:55 AM 8/6/08

   Nice comments & ideas :), keep it up & running. Moreover, the tested soil area on Mars is still so limited to whole Mars land. So, other places on Mars could be not Contaminated with this Perchlorate!

   Reply | Report Abuse | Link to this

10. 10. Mobocracy 08:55 PM 8/6/08

    Perchlorate is naturally occurring. This is from the USGS site:
    
    High Nitrate in the Desert? What's Going On?
    Desert vegetation at the Amargosa Desert Research Site
    Amargosa Desert, Nevada
    
    USGS scientists and their colleagues have unexpectedly found large concentrations of nitrate in desert subsoils. ..(shortened by me). However, the nitrate recently found is within a few meters of land surface and below the biologically active root zone. Contrary to conventional wisdom, small amounts of naturally occurring nitrate appear to have been leaching from soil layers and accumulating for thousands of years in the unsaturated zones of arid regions.

    Reply | Report Abuse | Link to this

11. 11. Bracken 01:23 PM 8/7/08

    Three points, 1. Would this oxidizing agent explain the anomalous Viking lander (1976) which seemed to indicate life in the sugar oxidation experiment?
    2. As unusual as this oxidizing agent is it doesn't argue against the presence of life on Mars. Many unusual oxidizing agents are used by Earth organisms (Nitrate, Ferric Iron). 3. It would appear that two major barriers to colonizing Mars are no longer a problem. Both water and abundant oxygen have been found,

    Reply | Report Abuse | Link to this

12. 12. Bracken 01:28 PM 8/7/08

    Three Points. 1) Would the presence of this oxidizing agent explain the anomalous data from the 1976 Viking lander that seemed to indicate life in the sugar oxidation experiment? 2) The presence of perchlorate does not argue against the presence of life on Mars, many earth organisms use novel oxidizing agents (Nitrate, Sulfate, Ferric Iron). 3) It would seem that two barriers to the colonization of Mars have been eliminated with the discovery of water and abundant oxygen which could be recovered from perchlorate.

    Reply | Report Abuse | Link to this

13. 13. Rob Hooft 02:54 PM 11/9/08

    Perchlorate is not a compound or a chemical. It is an ion, and its formula is ClO₄^-. To make a chemical, it needs a positive counter ion.

    Reply | Report Abuse | Link to this