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Signs of Liquid Water Found on Surface of Mars, Study Says

nytimes.com

101–110 of 193 posts

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#101

Earlier quoted context omitted.

And that someone seems to be this lady, with this most BAMF job responsibility ever: “These are ongoing conversations,” said Catharine A. Conley, NASA’s planetary protection officer, who coordinates the efforts to minimize the chances of life inadvertently crossing the solar system.

I must be missing something. How would you ever land men on mars if you are striving not to allow life to cross between planets?

[deleted]

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#102

Wouldn't it be bad if life forms are found in Mars, according to this? http://waitbutwhy.com/2014/05/fermi-paradox.html

Finding fossilized eukaryote cells on Mars wouldn't be the most glaring clue, that we're definitely going to destroy ourselves once technology is sufficiently advanced.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#103
post #99

Earlier quoted context omitted.

I must be missing something. How would you ever land men on mars if you are striving not to allow life to cross between planets?

The key word there is "inadvertently".

No, I got the key word. How the heck is that decision made? And by whom? Elon Musk gets ready to put a lander on Mars and there's a NASA office now that must give permission?

Sorry, still not making sense.

"Office of planetary probe sterilization" would be much more descriptive. Otherwise we're taking on a helluva lot more authority and prerogative than we probably should.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#104
post #85

Earlier quoted context omitted.

Speaking in Bayesian probability, it's bad if life forms found on Mars are more advanced than human, and good if it's much less advanced, or even very primitive (as it means the Great Filter might be at an earlier stage than us right now). And it won't be the former case, for obvious reason.

Finding life on Mars would still change one of the polynomials of the Drake Equation, which would shift upward the overall expected probability for intelligent life in the cosmos, which is probably what leonardzen means. But "we don't have enough data yet" still seems like a good answer to the Fermi Paradox anyway.

It would shift upward the overall expected probability for intelligent life at our level. However, since we have no evidence of life beyond our level of intelligence, it also increases the probability that civilizations will not survive long enough to become much more advanced than our civilization.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#105

Earlier quoted context omitted.

What an annoying meme. What part did you find so surprising that you want additional references, but couldn't find a better way to ask for them? As to the first part, there are uncountable examples of water-based life, and zero examples of non-water-based life. That doesn't rule out its existence, but basic chemistry makes it unlikely, and it won't look anything like life as we know it. No other liquid has the proper…

Start off by populating the universe with loose atoms. You're going to have quite a lot of H, some He, and ever decreasing quantities of larger atoms. The abundance of atoms in our galaxy by mass is 74% H, 24% He, 1% O, 0.5% C, 0.1% Ne & Fe & N, 0.05% Si & Mg & S. When you break it down by quantity of atoms, the spread only grows wider. 92% H, 7.5% He, 0.1% O, 0.05% C, 0.01% N & Ne, and ~0.003% Mg & Si & Fe & S. Now,…

Thanks for a detailed reply. My comment wasn't trying to be snarky, I really would like to know a reputable source for this statement.

As far as I understand it's much easier for us to know distribution of different elements that it is to know distribution of different molecules in the universe. I assumed that it wouldn't be that popular given that it does not take part in a nuclear fusion.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#106
post #12

R.S.L.s are treated as special regions that NASA’s current robotic explorers are barred from because the rovers were not thoroughly sterilized We're not going to sterilize our research equipment going to Mars and we're not going to search likely sites where we could find life because we don't want to contaminate them. And yet, looking for signs of life native to Mars (or even water which might support life) is the to…

Sterilization is not a binary thing, it's a matter of degrees. All of NASA's Mars rovers have been constructed in clean rooms and sterilized according to planetary protection protocols. But there are levels of such protocols and though the levels that have been used so far are quite high they are not sufficient to reduce the chance of some micro-organisms surviving the trip to Mars low enough to justify risking putting the rovers in environments with potential Martian life.

Additionally, only recently have we been able to construct rovers that could host the equipment necessary to reliably detect and study Martian life, so the level of sterilization that we've been using hasn't been a problem.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#107
post #12

R.S.L.s are treated as special regions that NASA’s current robotic explorers are barred from because the rovers were not thoroughly sterilized We're not going to sterilize our research equipment going to Mars and we're not going to search likely sites where we could find life because we don't want to contaminate them. And yet, looking for signs of life native to Mars (or even water which might support life) is the to…

There cannot be a manned mission to Mars with this policy.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#108
post #99

Earlier quoted context omitted.

The key word there is "inadvertently".

No, I got the key word. How the heck is that decision made? And by whom? Elon Musk gets ready to put a lander on Mars and there's a NASA office now that must give permission? Sorry, still not making sense. "Office of planetary probe sterilization" would be much more descriptive. Otherwise we're taking on a helluva lot more authority and prerogative than we probably should.

http://planetaryprotection.nasa.gov/about

Since all current private industry space efforts are still organized with NASA, I imagine this part of NASA is involved with efforts such as SpaceX as well.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#109
post #99

Earlier quoted context omitted.

The key word there is "inadvertently".

No, I got the key word. How the heck is that decision made? And by whom? Elon Musk gets ready to put a lander on Mars and there's a NASA office now that must give permission? Sorry, still not making sense. "Office of planetary probe sterilization" would be much more descriptive. Otherwise we're taking on a helluva lot more authority and prerogative than we probably should.

I'm puzzled about why the existence of guidelines for contamination of other planets would be surprising.

Note, the concept of "Planetary Protection" also applies to contamination in the reverse direction for sample-return missions, which are very much expected to be part of Mars 2020.

I didn't know this before looking, but it turns out there are UN agreements, and something called the "Outer Space Treaty" to which the U.S. is a signatory (1967). This treaty, in essence, prohibits "harmful contamination" of other planets. There is a body of scientists (a panel within COSPAR) which deliberates on contamination and issues guidelines in a timely way. ESA also has a policy. So there do seem to be players here that are larger than Elon Musk.

But these agreements are subject to revision and negotiation as more becomes known. Presumably something will be worked out as the reality comes nearer.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#110

Earlier quoted context omitted.

There have certainly been metioroids starting on Mars that made it to Earth without being sterilized[1]. Now, Earth does have a deeper gravity well which might make a difference but Earth microbes have had geological epochs to make the trip to Mars wheres you'd only expect a meteoroid to remain recognizable on Earth's surface for that long in comparison. So I figure that if contamination of Mars by Earth life was a p…

That makes sense, but wouldn't it be reasonable to assume that there's a major difference between natural seeding of life on other planets via meteors, and humans bringing it over while trying to find natural life? Furthermore, what if life on Mars were fragile enough that Earthly microscopic organisms destroyed it?

At some point we'll either have to either stop worrying about life on Mars being hidden under a rock somewhere or forever put a "humans keep out" sign on Mars.
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