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New Studies Doubt Mars Water Theory
An anonymous reader writes "Two groups of scientists have doubted the Mars rover scientists' theory that Mars was drenched with water for a significant time. If their dry Mars theories are supported, it is unlikely that life ever existed on Mars. The first group say that rock features that indicate water are actually caused by meteorite impacts. The second group argue that these features are caused by volcanic activity. Steve Squyres, the Mars rover lead scientist, is sticking by his original findings."
If the robot can hold out long enough, it may gather enough data to settle the debate.
More likely just enough to exacerbate it.
illegitimii non ingravare
Claims the rock features are the result of Intelligent Geology.
On the other hand, NASA scientists really need to promote the idea of finding life on Mars, no matter how unlikely it really is. Their projects cost vast amounts of money, and each time this starts to run short there is an announcement that they are about to find signs of life.
However, if we find life on our next door neighbor, we have some explaining to do. How did life get there? Was it transplanted from earth? Or was earth life transplanted from Mars? If life can propogate across the void of space between earth and Mars, what's to stop it from propogating across solar systems and perhaps even galaxies in astronomical time scales? How old is life anyway, and where did it really come from?
Well, the chances of Mars life reaching Earth, or of Earth life reaching Mars, are pretty good. The two planets are close together; chances are that sooner or later a rock is going to get knocked from one to the other with some spores on board. I would not be at all surprised to find that Mars life (if it exists) and Earth life share a common ancestry.
However, the interstellar spread of life seems less likely to me. While it's quite likely that a rock from Earth might by chance find its way to Mars, it's very unlikely that it would ever escape the solar system entirely. The energy needed to leave the Sun behind is enormous, and the odds of a loose rock ever actually getting somewhere of interest are minute. If life spreads from star to star, it'll do so because it's evolved a form capable of building starships.
Now, if we found HUMAN life on Mars, that would really destroy all of the ongoing theories of the origins of life on earth. Either we are a spacefaring species and thus earth is not our home, or somehow, despite all odds, humanity has evolved on two separate planets that just happen to be right next to each other.
I don't think anyone sane is suggesting that that's likely to happen.
Real Daleks don't climb stairs - they level the building.
If life can propogate across the void of space between earth and Mars, what's to stop it from propogating across solar systems and perhaps even galaxies in astronomical time scales?
The nearest galaxy to ours is 25,000 ly away. Even assuming a speed of 1% of the speed of light, which is very fast, it would take 2.5 million years to get there. Considering 0.01c is over 1000 times faster than the escape velocity of the galaxy at the position of the sun, it's not a very realistic speed, so the actual time will be much larger. If random bits of life go off in random directions they're unlikely to meet anything any time soon, so it will probably take billions of years before something goes in the right direction and then billions of years for it to get there - astronomical time scales would be at most 10 billions years or so(the universe is less than 15 billion years old by the last estimate I read, and it takes some time for galaxies, stars, planets and finally life to form), so the chances are very very slim, although prehaps not impossible.
Life transporting between stars is easy enough though. A meteor hits earth, a bit of rock flies off and ends up in either earth or solar orbit (probably wouldn't fly off fast enough to leave the solar system), the bit of rock then gets hit by a comet on a parabolic course from the oort cloud going in towards the sun and then out towards another star, the rock sticks to the comet, is carried to the other star where it crashes into a planet. Over the 4 billions years or so that life has existed on earth, that could easilly have happened.
See, the chances of life spontaneously being created on a planet is so astronomically small as to be almost impossible.
That's nuts. The chances of life arising spontaneously (note: not "being created") are quite high. The individual steps are reproducible in the lab, and the overall process is quite simple. Given a heterogeneous goop capable of forming complex molecules (e.g. water with a normal assortment of space stuff), a flow of energy (source and sink) and enough time, life is pretty much inevitable.
-- MarkusQ
cold is a relative term for when matter has lower kinetic energy than you do (or something you're referring to does). what do you mean when you say the cold of space?
p.s. this is an actual question, not a troll
if i'm not immortal, what's the point of living?
...te?
Sorry to rain on everyone's parades here, but to find any signs of life on Mars would really damage the current theory of how life got to be here.
Why? The "current theory" is that life arose from complex molecules eventually forming reproducing organisms, evolving over time to the level of complexity we see today on Earth. How would the discovery that something similar happened on Mars damage that theory in the least? Besides, the invalidation of theories is a big part of scientific progress, so if anything, it's a good day for science when a theory is disproven.
See, the chances of life spontaneously being created on a planet is so astronomically small as to be almost impossible.
First, you can't just state facts like that without any hint that they are supported by evidence (to quote Sagan, absence of evidence is not evidence of absence). Second, even if we are to accept this as truth, just how small are these chances, numerically? Third, it's entirely possible for two next door neighbours to both win the lottery in the same week.
However, if we find life on our next door neighbor, we have some explaining to do.
Sure we do. And if we don't find life there, we still have some explaining to do. That's the purpose of science: to explain.
All of a sudden, earth won't seem so unique anymore. And we'll start wondering why SETI hasn't turned anything up yet.
Sounds like a creationist fnord to me. Life on Earth only seems unique because so far it's the only example we have. To flipside a previous analogy, it's possible for an entire city to go a hundred years without any of its inhabitants winning the lottery.
Now, if we found HUMAN life on Mars, that would really destroy all of the ongoing theories of the origins of life on earth.
Back on topic. No one said anything about human life. In any case, I'd like to hear about this supposed plethora of ongoing theories of the origins of life are. Intelligent design is going out of style.
If you're not part of the solution, you're part of the precipitate.
Nasa Mars articles are subtly and covertly constrained by NASA media censors because of the political and funding sensitivites ?
If so, thats really bad, and should be stopped.If they are not constrained, then the scientists themselves give the perception of ignoring ESA data or references, which I find impossible to believe.
Are my observations at fault? Is there a pragmatic and reasonable explanation why this debate seems so oddly limited in scope and reference to ESA etc?
There is no god; get over it already! Never exchange a walk on part in the war, for a lead role in a cage.
It's kind of old (and oft duplicated) news that you can make the basic building blocks by just stewing goo; likewise, the fact that once you have "life" of some form it will evolve quite rapidly (if it breeds rapidly) is a pretty standard classroom demonstration.
The only part that is really recent is that replication itself starts easily from the goo. The only "trick" seems to be cycling the reagents in & out (think a tidal pool) and using lots of little samples (again, think a tidal pool) rather than one big one. A quick google turns up lots of examples which (if you piece them together) cover the whole gamut. A small sampling:
--MarkusQ