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Is the experiment to find water on mars by NASA is most idiotic one

  1. Jul 28, 2013 #1
    Is the experiment to find water on Mars by NASA is most idiotic experiment ever conducted by mankind.

    I mean, spacecraft send to Mars use hydrocarbons or hydrogen as fuel; this fuels byproduct is water. So there is a greater chance that after some exploration if NASA find traces of water on Mars that could be from the space craft itself( as the byproduct of fuel combustion is water)
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  3. Jul 28, 2013 #2


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    They aren't looking for water on Mars. They are looking for evidence that large amounts of liquid water existed in the past. Lots of water already exists as ice in the ice caps. In addition trace amounts of water vapor exist in the atmosphere.

    See here: http://en.wikipedia.org/wiki/Water_on_Mars
  4. Jul 29, 2013 #3


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    Most of the recent landers didn't use engines to land anyway and even for those that did, the water vapor would never have condensed.

    [Edit] And rocket scientists aren't that stupid.
    Last edited: Jul 29, 2013
  5. Jul 29, 2013 #4


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    Mars is an exciting laboratory to explore. It is similar to earth, has a wide variety of terrain and geology, and widely believed to have held large amounts of water for the first billion years or so of its existence. Thus, it is an ideal place to search for evidence of exobiology - at least in the fossil record. This would obviously be a find of enormous significance. It would be disappointing to come up empty, but, entirely worth the expense. At very least we will learn how not to look for life. I am, however, still optimistic it will produce results.
  6. Jul 29, 2013 #5
    I mean that traces of water in atmosphere may be from rocket's fuel burned

    Every Hydrocarbon , hydrogen, H2O2, even ammonia as fuel produces water vapor as exhaust
  7. Jul 29, 2013 #6


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    You might try calculating an upper bound on the amount of water introduced into the Martian atmosphere in this way. If measurements indicate much more water than that, then we can conclude that there was water there before the probe arrived; if not the results are inconclusive. That's the way it is with almost all scientific experiments: The press reports "Scientists have found that there is no <something>", but when you read the actual paper, you find that the scientists are making the more precise claim "Our experiment doesn't prove that there is no <something>, but it show that if <something> does exist, there's no more than <some small number> of it".

    I expect that if you do the calculation you'll find that even if the upper bound is high by several decimal orders of magnitude, we're dealing with a reasonably well-designed experiment.
  8. Jul 29, 2013 #7

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    Do the math. Let's just look at Mars' atmosphere. The mass of the Martian atmosphere is around 2.5×1016 kg. Most the atmosphere is CO2, but a small trace (210 ppm) is water. Mars' atmosphere alone contains about 5.2×1012 kg of water. Compare that to a fully loaded Saturn V rocket at takeoff, about 2.9×106 kg. The water in Mars' atmosphere is the same mass as 1.7 million Saturn V rockets at takeoff.

    Missions to Mars don't use Saturn V rockets. They use smaller ones. Almost all of any rocket's mass is consumed during launch. For missions to Mars, a tiny bit was used to send the vehicle on the way to Mars. An even tinier bit was used to put vehicles into orbit about Mars. None of these tiny bits contributed to Mars' atmosphere. The only part that did was the extremely tiny bit used to get vehicles from Mars entry to the surface, and that was only done on a handful of missions or so.

    We would have needed to have sent billions of missions to Mars for those Mars missions to explain the amount of water in Mars' atmosphere. We didn't do that.

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