Italian magazine claims Phoenix contaminated Mars with terrestrial bacteria |
Italian magazine claims Phoenix contaminated Mars with terrestrial bacteria |
Sep 1 2008, 05:04 PM
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#1
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Member Group: Members Posts: 109 Joined: 20-January 07 From: Milano, ITALY Member No.: 1633 |
I have just read a short story by Alex Saragosa published on issue 1067 (29 Aug 2008, pag. 61) of the italian magazine "il venerdì", a Friday supplement of the major national newspaper la repubblica. The story, titled "I batteri terrestri hanno invaso il pianeta rosso" (terrestrial bacteria have invaded the red planet), claims a group of JPL bilogists analyzed samples from the room where Phoenix was assembled and found 26,000 bacterial cells per square meter from 100 different species, including highly radiation resistant Bacillus pumilis. According to the story, these bacteria may have survived the trip to Mars.
I have never heard anything similar from reliable sources (i.e. anything but la Repubblica) . Any info? Paolo Amoroso -------------------- Avventure Planetarie - Blog sulla comunicazione e divulgazione scientifica
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Sep 1 2008, 05:32 PM
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
Well - those numbers do sound high - but let's be realistic about this - Bacteria made it onto Mars with plenty of landers, successful and otherwise, over the past 40 years.
Doug |
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Sep 1 2008, 05:41 PM
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#3
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Senior Member Group: Members Posts: 2530 Joined: 20-April 05 Member No.: 321 |
Yes, the problem would only be if they are able to travel away from their sites. If they can't reproduce and/or travel downwind and reproduce in the a location, there's no real harm done.
Of course, if putative martian biota can't travel and reproduce in a new location, then Mars has to be devoid of viable native life. |
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Sep 1 2008, 05:54 PM
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#4
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Member Group: Members Posts: 213 Joined: 21-January 07 From: Wigan, England Member No.: 1638 |
I have never heard anything similar from reliable sources (i.e. anything but la Repubblica) . Any info? I recall reading in Science (or similar rag) that a team from JPL originally found 100,000 microbes per sq/m just a few months before launch, and thus requested a more aggressive sterilization program. |
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Sep 1 2008, 06:02 PM
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#5
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Member Group: Members Posts: 101 Joined: 29-January 06 Member No.: 667 |
NASA Astrobiology Magazine
QUOTE AM: What’s the requirement for the upcoming Phoenix mission? CC: Phoenix is going to a place where there is ice beneath the surface. It will not be going to a place where there is ice on the surface. And Phoenix as a lander is a fairly light spacecraft. It doesn’t have a lot of big heavy massive things in it. It also doesn’t have any thermonuclear generators, so it will not be producing its own heat; it runs on solar panels. So based on calculations that were done by the project to document all this to the appropriate level of confidence, the spacecraft itself is not being required to be sterilized because the martian surface at its landing site is not considered to be a special region. |
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Sep 1 2008, 06:08 PM
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#6
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Member Group: Members Posts: 101 Joined: 29-January 06 Member No.: 667 |
New Scientist (so be skeptical): Could microbes on Phoenix survive on Mars?
QUOTE To fill this gap, a team from NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, US, took a census of all microbial life living in the Phoenix assembly room as the mission progressed. About four months before launch, in April 2007, at least 100,000 microbial cells – including 132 different kinds of bacteria – covered each square metre of the room. In June, the JPL team found evidence for at least 35,000 cells per square metre, belonging to 45 different kinds of bacteria – a decrease most likely due to stepped-up cleaning efforts. Around the time of launch in August, the room boasted at least 26,000 cells per square metre and 100 kinds of bacteria. This sounds like the source of the Italian story. |
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Sep 1 2008, 06:54 PM
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#7
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Merciless Robot Group: Admin Posts: 8785 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Doug's right, though. You can't get rid of all the little beggars, ever. Mars hasn't been technically pristine since the first thing we sent from Earth arrived.
BTW, didn't one or more of the early Soviet Mars boosters impact Mars as well in the '60s? You KNOW those things weren't even close to sterile. Phoenix & indeed every other lander is squeaky-clean by comparison. -------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Sep 1 2008, 07:05 PM
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#8
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Senior Member Group: Members Posts: 1229 Joined: 24-December 05 From: The blue one in between the yellow and red ones. Member No.: 618 |
Ominous voice of Joe Friday: With a bacterium, it only takes one.
Dummm... de dummdumm.... -------------------- My Grandpa goes to Mars every day and all I get are these lousy T-shirts!
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Sep 1 2008, 07:42 PM
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#9
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Senior Member Group: Members Posts: 2542 Joined: 13-September 05 Member No.: 497 |
...a group of JPL bilogists analyzed samples from the room where Phoenix was assembled and found 26,000 bacterial cells per square meter from 100 different species... The bioburden of the room is fairly irrelevant, as the requirement (<300 spores/m2 for a Class IV Mars lander mission) is obviously on the stuff going to Mars, which is much more extensively cleaned than the room is. -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
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Sep 1 2008, 10:17 PM
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#10
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Junior Member Group: Members Posts: 21 Joined: 6-August 08 From: Augusta, Maine Member No.: 4305 |
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Sep 1 2008, 11:00 PM
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Member Group: Members Posts: 160 Joined: 4-July 05 From: Huntington Beach, CA, USA Member No.: 429 |
I think it's Bacillus pumilus (both words ending with "us"). Google easily finds an article mentioning Bacillus pumilus and JPL (Phoenix is not mentioned):
http://www.plosone.org/article/info:doi%2F...al.pone.0000928 You may prefer to read the PDF version, it looks nicer than the web page. |
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Sep 2 2008, 10:46 AM
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Senior Member Group: Members Posts: 1465 Joined: 9-February 04 From: Columbus OH USA Member No.: 13 |
What's the max surface temperature on Mars--0C? And at the Phoenix site -20C? Any bacteria aren't going anywhere fast.
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Sep 2 2008, 11:21 AM
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
If you're lucky, at summer, near the equator - maybe 20degC
Doug |
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Sep 3 2008, 03:07 PM
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Member Group: Members Posts: 401 Joined: 5-January 07 From: Manchester England Member No.: 1563 |
Yes but regions that have those kinds of ground temperatures have little unbound H2O and visa versa. However there hasn't been found a hard lower temperature limit to biological processes as far as I know. Everything just gets slower and slower and activity tails off (even for the hardiest), without ever completely stopping, around -15 to - 20. There is some activity going on even at minus 40 deg C. So it's right down at the edge of couldn't happen, but on an unusually warm day if the right little critter got carried there, maybe......
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Sep 3 2008, 05:31 PM
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Junior Member Group: Members Posts: 96 Joined: 11-February 04 Member No.: 24 |
There is some activity going on even at minus 40 deg C. So it's right down at the edge of couldn't happen, but on an unusually warm day if the right little critter got carried there, maybe...... Your little critter must endure the following obstacles on the Martian surface : 1) low temperature 2) no liquid water because the atmospheric pressure is too low 3) strong oxidants like perchlorates 4) ionizing radiation, e.g. secondary cosmic rays and short wavelength ultraviolet You can probably find some weird extremophile that could survive each of the above obstacles but is there anything recognized as "life" that can survive all four? I suspect not. If life exists on Mars it would have to be deep under the surface (deep dark life metabolizing hydrogen). I might add that a similiar argument could be invoked for life on Venus, i.e. it's deep under the surface. However I doubt that we'll have the technology to detect Venusian life anytime soon. |
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