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NASA's Mars News Is Not Life, But Perchlorate

leighklotz writes "In an update to the little green men story of not-life-on-Mars, NASA has twittered: 'The buzz this weekend was due to an interesting soil chemistry finding, still preliminary, but now avail here:' where 'here' is NASA Spacecraft Analyzing Martian Soil Data. The exciting bit: 'Within the last month, two samples have been analyzed by the Wet Chemistry Lab of the spacecraft's Microscopy, Electrochemistry, and Conductivity Analyzer, or MECA, suggesting one of the soil constituents may be perchlorate, a highly oxidizing substance.' Also, 'NASA will hold a media teleconference on Tuesday, Aug. 5, at 2 p.m. EDT, to discuss these recent science activities.'"

22 of 289 comments (clear)

  1. Contamination? by morgan_greywolf · · Score: 5, Interesting

    Perhaps I'm missing something obvious here, but how seriously are they considering the possibility of contamination? Because unless I'm remembering something wrong, perchlorates are most excellent oxidizers and hence commonly used in, oh, say, solid rocket fuel, among other things.

    1. Re:Contamination? by smolloy · · Score: 5, Informative

      These are intermediate results, and should be treated as such. From TFA,

      The team also is working to totally exonerate any possibility of the perchlorate readings being influenced by terrestrial sources which may have migrated from the spacecraft, either into samples or into the instrumentation.

    2. Re:Contamination? by MagusSlurpy · · Score: 5, Insightful

      You are right, and generally, the Space Shuttle missions are launched using 2 solid-fuel rockets, composed primarily of ammonium perchlorate, so it is certainly a possibility; but one should consider that if the probe itself is contaminated, it should be detecting perchlorates in all of the samples. . .

      --
      My sister opened a computer store in Hawaii. She sells C shells by the seashore.
    3. Re:Contamination? by silentben · · Score: 5, Informative

      Not likely - yes, perchlorate is used in solid rocket fuel, but solid rocket fuel would not be used for a landing because you can't control the burn. It is only really good as a powerful launch vehicle because it can burn fast and hot, but you can't easily turn it on or off or control the rate of burn. For landings and precision manuveuring liquid fuels such as liquid hydrogen and oxygen are much more common.

    4. Re:Contamination? by jon_cooper · · Score: 5, Funny

      Don't be silly. This is obvious evidence that extra-terrestrials have been on Mars and left behind perchlorate traces from their rockets. Either that, or Martians have just blasted off somewhere in their rockets. Wonder where they've gone?

    5. Re:Contamination? by silentben · · Score: 5, Informative

      This means that neither the propellant or the resultant chemicals are perchlorates, so this substance can be ruled out as a contaminant due to propellants. So contamination theory is out. See also the following excerpt from the same site you sourced:

      Will Phoenix's descent thrusters alter the composition of its landing site?
      Altering the chemistry of our landing site due to our thruster exhaust is unavoidable. The Phoenix Lander uses hydrazine, a hypergolic propellant that turns into ammonia during combustion. So essentially, we are spraying the surface with ammonia and a small amount of hydrazine that was not combusted. The way we get around that is by 1) knowing that we are going to be producing ammonia and 2) by designing the wet chemistry cells to carefully quantify the amount of ammonia in the regolith. We then use this information to interpret our other results.

    6. Re:Contamination? by amliebsch · · Score: 5, Funny

      So, you're saying that all we'd have to do is...start...the reactor?

      --
      If you don't know where you are going, you will wind up somewhere else.
    7. Re:Contamination? by Anonymous Coward · · Score: 5, Informative

      Scientific American reported that "The fuel in the thrusters that Phoenix used to land on Mars was made of hydrazine, not perchlorate."
      http://www.sciam.com/blog/60-second-science/post.cfm?id=perchlorate-found-on-mars-makes-soi-2008-08-04

    8. Re:Contamination? by vrmlguy · · Score: 5, Funny

      These are intermediate results, and should be treated as such. From TFA,

      The team also is working to totally exonerate any possibility of the perchlorate readings being influenced by terrestrial sources which may have migrated from the spacecraft, either into samples or into the instrumentation.

      Wouldn't it be amusing if some joker, before launch, had sprinkled a handful of dirt into the analysis chambers? (And by "amusing", I mean in the "How close do you think I can steer this ocean liner to that iceberg?" sort of way.)

      --
      Nothing for 6-digit uids?
    9. Re:Contamination? by roguetrick · · Score: 5, Funny

      Quit giving the martians ideas.

      --
      -The world would be a better place if everyone had a hoverboard
  2. Holy cow, do you know what what this MEANS? by greenguy · · Score: 5, Funny

    Yeah, me neither.

    --
    What if I do the same thing, and I do get different results?
    1. Re:Holy cow, do you know what what this MEANS? by chord.wav · · Score: 5, Informative

      Wikipedia is your friend:
      http://en.wikipedia.org/wiki/Perchlorate

      Perchlorates are the salts derived from perchloric acid (HClO4). They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to treat thyroid gland disorders. They are also used as an oxidizer in rocket fuel and explosives and can be found in airbags, fireworks, and Chilean fertilizers.

      Now, do you know what that means?? We could have tons of Chilean fertilizers YEAH!!!!

    2. Re:Holy cow, do you know what what this MEANS? by sheehaje · · Score: 5, Funny

      Chilean fertilizer is a euphemism for bird shit.

      Holy Cow, there are birds on Mars...

      Slashdot.... deductive reasoning at it's best.

    3. Re:Holy cow, do you know what what this MEANS? by Reverend528 · · Score: 5, Insightful

      It means that a planet made of rust has an oxidizing agent in the soil. I could've told you that without going to mars.

  3. Why this is important to non-chemists by bsDaemon · · Score: 5, Informative

    OK, so at first I read "highly oxodizing" and was thought, "neat; now they know why Mars is rust colored." However, even after RTFA, I was still clueless as to why I should care. Luckily, Wikipedia comes to the rescue.

    From the wiki:

    Both potassium perchlorate (KClO4) and ammonium perchlorate (NH4ClO4) are used extensively within the pyrotechnics industry, whereas ammonium perchlorate is a component of solid rocket fuel. Lithium perchlorate, which decomposes exothermically to give oxygen, is used in oxygen "candles" on spacecraft, submarines and in other esoteric situations where a reliable backup or supplementary oxygen supply is needed. Most perchlorate salts are soluble in water.

    So, it seems to me that the important discovery is that there could be a relatively massive supply of a chemical compound which is able to produce breathable oxygen, if and when we can ever get people to Mars. If this is indeed the case, then YES, this is exciting news, a whole lot more important than why Mars is red, and is on the level of the sort of thing that the President might want to know about.

  4. Perchlorate by clang_jangle · · Score: 5, Funny

    I used to perchlorate my coffee every morning, but then I read that the drip method actually gives you more caffeine. So the mars people are stuck with 1960s technology then?

    --
    Caveat Utilitor
  5. Oxygen Generation by Rand310 · · Score: 5, Informative

    Perchlorate does three things:

    -Treats thyroid gland disorders

    -Used as rocket fuel

    -Used in generating oxygen (O2) chemically

    Seems like good happenstance to land on a planet with frozen water on tracts of rocket fuel and solid oxygen-generating salts.

    http://en.wikipedia.org/wiki/Chemical_oxygen_generator

  6. Re:Is this considered fuel for a return trip? by loraksus · · Score: 5, Informative

    So as I understand it, perchlorate can be used to make rocket fuel.

    Sort of -
    Perchlorates are oxidizers, which technically are not the "fuel" in the reaction. Oxidzers are, however, the stuff that is somewhat dangerous to handle / transport - the fuel is normally a rather ordinary substance (i.e. in black powder the fuel is charcoal, in modern rockets, powdered aluminum)

    A catalyst is required, but the less you have to ship to mars, the easier it is...

    --
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  7. Mars + highly oxidizing substance + Governator by buddahrock · · Score: 5, Funny

    Maybe the President just needed a few days to rent and watch Total Recall, then convince Governor Schwarzenegger to go to Mars and start the ancient Martian machine that creates a breathable atmosphere.

  8. Or maybe not? by anadem · · Score: 5, Interesting

    Or maybe not, based on data from the Viking missions:

    http://www.space.com/news/spacehistory/viking_life_010728-1.html

    "Photos taken on Mars' surface of a Viking magnetic experiment on both landers show material clinging to the magnets. That suggests to Levin that whatever the surface processes are on Mars, they are not innately highly oxidizing. A highly oxidizing soil would convert magnetized materials to oxidized forms. Therefore, the magnet would be free of such particles.

    "Similarly, the Mars Pathfinder mission in 1997, Levin added, also had significant amounts of magnetic material adhering to magnets attached to the spacecraft.

    "Levin said that the paradigm of a Mars sterilized by a highly oxidizing surface is "too embedded in our scientific fabric to be set aside even by demonstrated proofs. He points to a John F. Kennedy quote that says 'the great enemy of truth is often not the lie --deliberate, contrived and dishonest -- but the myth -- persistent, persuasive and unrealistic.'"

  9. News Conference on Tuesday LunchTime by wooferhound · · Score: 5, Informative

    The News Conference is on Tuesday, Aug. 5, at 2 p.m. EDT, but it's not on TV, it's streaming audio from Here...
    http://www.nasa.gov/news/media/newsaudio/index.html

    --
    We are Dead Stars looking back Up at the Sky
  10. This would clear up a few things by Eicos · · Score: 5, Informative

    Back in the 70's, NASA ran an experiment on one of the Viking landers to try to see if there was any life on Mars. The experiment contained some radiolabeled "food," to which a sample of regolith and water would be added. If radiolabeled gas evolved from the resulting mixture and was detected, it would be taken as a sign that some kind of native microbe was eating the food and emitting the gas as a byproduct of anaerobic respiration. And in fact, the experiment did detect radiolabeled gas. However, none of the other analyses turned up positive, including the mass spectrometer. So scientists floated an alternative theory: that the Martian regolith contained some kind of oxidizing agent, which would have explained both the evolution of radiolabeled gas, and the absence of life on Mars. Most scientists accepted this theory, but even to this day, there were a few who believed it was a little bit too convenient, and that the labeled release experiment had actually turned up evidence of life. The discovery of perchlorate, a strong oxidizing agent, would put that speculation to rest.