Martian life

Does anyone know what happened to what scientists called fossilized nanobacteria on an asteroid from Mars. I heard something about it possibly being a mineral deposit, but I haven’t heard for sure.

I don’t think I’ve ever heard anything for sure either. I know there were some fairly serious doubts raised – indications that it might have been non-biologically caused – but I don’t think there really has been any resolution.

The microformations are pretty clearly not biological. They are just how some minerals precipitated out of the water that was there at the time. They were shown a lot on the news and in the magazines because the real evidence is pretty technical and dull. As I understand it, the ratios of oxygen isotopes found in the sample were consistent with the ratios found in Earthly rocks that were formed with biological activity. Hardly earth shattering. Last I heard the jury was still out. It is very difficult to make a valid inference based upon one specimen. We need more samples.

The biggest reason that the issue of the Martian “fossils” petered out was a sequence of refutations of the underlying assumptions made by the investigators. The hydrogen/carbon ratios were not incorrect, but the inference that they must have been organic was overstated. The limits of heating required to support survival through re-entry were not impossible, but were very close to the heat necessary to create some of the compounds found without life processes being involved. The size and shape of the “fossils” was quite dissimilar to the type of bacteria they “resembled” in the opinion of the discoverers. In the end, the possibility is not entirely eliminated that these are traces of life, but it falls far short of anything resembling “proof” that there was life on Mars. There was some backpedaling by some of the institutions involved, as well, over the issue of publication before peer review.

<p align=“center”>Tris</p>

On the other hand, I read a report a few weeks ago of another discovery which tends to support the notion that this is fossilized microbial life. But yeah, at this point it’s still speculation.

Guess we’ll just have to do a sample-return mission to Mars, then. (Go ahead, twist my arm.)

All:

Please forgive and correct my ignorance. How exactly did a rock from Mars find its way to Antarctica?

CONTESTANT #3(or whatever your name may be today): Please interpret my use of the word “All”, above as intending to exclude you. No offense.


Well, maybe a little offense . . .

Aliens probably dropped one of their souveniers on their way to eat seafood at the Crab Nebula.

Seriously, “scientists” (I put that in quotes not because they’re not, but because I don’t recall who they were) have identified a number of meteors that they believe found their way from Mars as a result of catastrophic cue-balling from some renegade asteroid. Part of the impact explodes outward fast enough to reach escape velocity, where it drifts along in space until some unwary planet or moon tugs it ever closer.

This particular rock seems to have been blasted off Mars by a big asteroid strike about four billion years ago. It also seems to have finally bumped into Earth about fifty thousand years ago. (These numbers are approximate, as I’m just typing from memory.) Antartica is a great place to find meteorites. Think about it-- if you find a rock on top of the ice sheet it MUST have landed there from someplace else, and pretty recently too. If you find a rock in Maine you will never give it a second glance.

You could legitimately ask how “they” know that this rock is from Mars. I know the answer has to do with isotope ratios compared to Earth rocks, “normal” meteorites, and Viking data, but the details were so dull they slipped clear out of my mind…

Kaylasdad asked:

Damned foreign taxi drivers!

If the only thing we have to prove that this rock came from Mars are similar isotopes. Isn’t it equally possible that this came from some entirely new solar system?

Occam, use your razor.

If we find a McDonald’s hamburger wrapper and there is one of those fast-food outlets on the next block, we have no need to postulate that a trucker brought it over from three states away.

Except all McDonalds’ are equally spaced one block apart.

A now-chastened kaylasdad99 earlier posted:

While I expect that most people on this thread have been able to deduce fairly easily why I might post such a statement, my reading of certain responses to jedi667 on another thread have opened my eyes to the fact that attempts to exclude any individual from responding to a post are, strictly speaking, against the rules.

My apologies.

Besides, if I get away with it, jedi667 will have ammo to use in any whining he may want to do about not being treated fairly. I’d really hate to have that on my conscience.
Jedi667, feel free to respond. :wink:

Another proof the rock came from Mars are tiny air bubbles trapped inside. When analyzed they were found to be the exact same chemical composition of the Martian atmosphere as discovered by Viking 1 and 2 in 1976.

It would’ve been nice if that rock had had traces of microbial life. But since we’ve found all manner of subterranean microbial life here on Earth in places where almost no one expected to find it (nearly two miles down in a South African gold mine, for example), we definitely need to go back and simply drill deeper holes. The latest Mars probe aimed at the South Pole is supposed to do something like that, right?


Those who do not learn from the past are condemned to relive it. Georges Santayana