'Life on Mars' Meteorite Rejected After 10 Years

An anonymous reader writes "Ten years ago, NASA announced that the Martian meteorite ALH84001 showed evidence of life on Mars. The announcement made headlines around the world, and even prompted President Clinton to make a statement. Ten years later, most scientists believe that everything in the meteorite can be explained by non-biological processes. "We certainly have not convinced the community, and that's been a little bit disappointing," said David McKay, a scientist behind the 'life on Mars' paper. Unfortunately, David McKay's own brother is one of his critics. "He [David] got a little testy about the results we were getting," said Gordon McKay. "What we have shown is that it is possible to form these things inorganically.""

Comments

Re:The hard truth

[Anonymous Coward]

No one wants to admit life started out there somewhere. For all we know the meteorites seeded life on Earth... and elsewhere. Why is it so hard for people to believe life exists beyond earth?

Just because people believe life started elsewhere doesn't mean that this rock is an example of life. Wanting life to exist elsewhere does not account for good scientific judgement. I fear that Mr. McKay has much of the former but little of the latter.

Re:The hard truth

[Anonymous Coward]

This stuff is science, not religion. All that's being said in the article is that there are explanations for the contents of that chunk of rock other than life. That doesn't rule out the possibility that life was involved, but it does rule out the meteorite as proof that there was life. So, we're back where we were before: no one knows for sure.

burden of proof

[Bartmoss]

Just because these things can be formed inorganically doesn't mean they were. Still the burden of proof definitely rests on those who says it is organic in origin. Especially now.

Luckily, just because the meteor may not have signs of former life, doesn't mean mars never had any. It would be really sad if our solar system turned out to be sterile.

cool science

[fermion]

This is the kind of subtlety that people seem to miss in science. Just because something could be true, does not mean it is true. In this case the samples in question could have been formed by an organic process, but they did not have to be. And since the overwhelming evidence is that there is no life on mars, and in fact we have no real process as yet that would have developed life on mars, the reasonable person still concludes that life probably does not exist. Now some people just are going to believe for personal reasons, and that is cool. Those people need to look for evidence in an attempt to prove their case. But this particular piece of evidence appears to have been taken out of contention.

Re:cool science

[lawpoop]

I take a somewhat different tack.

It is true that we do find life in some rather inhospitable places, like highly radioactive nuclear reactor cores, inside solid rock, in boiling steam vents, metabolizing sulfur -- but does that mean life can arise in such places, or does it require particular conditions to arise, and then it is capable of evolving to adapt to such harsh environments? The basic amino acids that constitute life do not survive in such environments. The living organisms which live in such environments have special mechanisms to protect and repair their delicate parts.

But the places where we find the most diversity of life is in the oceans and the tropical rain forests. That tells me there are a few elements that life really wants -- a relatively small temperature window, light, and most importantly water. The oceans are water, and the tropical rain forests are almost always at 100% humidity. I would even say that the temperature range that life wants is the range of liquid water. Taking this a step further, I would say that anywhere we find liquid water, we will find life.

Re:The hard truth

[Reality Master 101]

No one wants to admit life started out there somewhere. For all we know the meteorites seeded life on Earth... and elsewhere.

Er, exactly how would life begin on a meteorite? Exactly what chemistry would allow that to happen? I think it's a tad more likely that life would begin on a planet with the requisite natural resources.

The probabilities and facts dictate the earth is not the center of the universe.

We have absolutely zero evidence for life on planets other than earth. On the other hand, we have considerable evidence that we're alone in the galaxy (other galaxies are too far away to know anything about).

I for one think it would be good for mankind to have a significant first contact with a superior race. At least then we can then look to exploration and not war to keep us occupied while we grow up.

I for one think magic wands would be good for mankind as well. Then we could keep busy with our wands and not war. It would also eliminate resource limitations, which are fundamentally the reason for war. Magic wands are about as likely as alien life, so why not go for broke?

Re:The hard truth

[4D6963]

For all we know the meteorites seeded life on Earth

So far the theory of panspermia is very far from proven, and the most widely accepted theory about the formation of life on earth is not panspermia but chemical reactions forming aminate acids, or somethnig of this kind.

Why is it so hard for people to believe life exists beyond earth?

When it comes to science, thou shalt ban the verb 'to believe' out of thy vocabulary.

I for one think it would be good for mankind to have a significant first contact with a superior race

Why do people systematically consider that an extraterrestrial race would have to be superior to us in the same way that we are superior to the rest of animals? Keep us occupied while we grow up? What's making you think that we're growing up? Our nature is immuable, the only way we can give ourselves the feeling of evolving is through the evolution of our civilization, but that's not going to make us closer to any hypothetical superior extraterrestrial race, if there even can be such a thing as animals significantly superior to us. It seems that the idea of us being probably the most evolved life form possible has went through relatively few people's minds.

Back to the topic, scientists have no trouble admitting some forms of life might exist or might have existed in the universe, even inside our very own solar system. But the object of this article is about determining whether this precise piece of rock reveals the existence of any actual extraterrestrial form of life, it's not about determining whether there could or could not have been life in the Universe, nor even on Mars.

It's all about this precise rock.

I can't help but think of using this for religion

[deft]

NOT getting the results that most of the scientific community would REALLY want as such a cool discovery that could advance thinking is a great example to show religious types.

This is what it looks like when the process beats an idea with logic and testing and eventually disproves what they really wanted to be true. In things like "intelligent design" it could never ever come out with such a neutral result agreed upon by people who may have been very much for the idea the entire time. No lying, not falsifying, no BS logic.... just the truth through science.

I applaud their dilligence, and wonder if that guy in Vegas who one the "when will life on other planets be dicovered" jackpot gets to keep his $$$ :)