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Evidence of Bacterial Life on Europa
AaronW writes: "According to this article at newscientist.com, the rosy color of Europa may be caused by bacteria. Apparently the previously unexplained infra-red signature matches that of extremophile bacteria found here on Earth."
except Europa.
Method of processing duck feet
If there is a liquid zone underneath the ice, it could be considered an atmosphere (well, you know what I'm saying).
Try this, and this, and this. (Just a little googleing ;-)
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
Ya know... when life started on earth... it was pretty damn inhospitable here too. There was no oxygen, no water (...oxygen), so our standards of "inhospitable" aren't universal... I mean, there are bacteria in your ass, and who can think of a more inhospitable place than that?!?
let's us not jump to early conclusions; i always tend to find these kind of articles very hope-giving while they are often very inconclusive. A while ago we could read about waterflows on mars (with pictures!) that later turned out to be carbon?dioxide? jets if i remember correctly. Those were some nice pictures, don't get me wrong and this article sure lightens up the discussion of extraterrestial life (not intelligence, life, note the difference please) that could possible be related to earth life (asteroids and all) which could give us some insight in the development of earth-life. :)
So, interesting, but don't get your hopes up too much
"We live in our minds, and existance is the attempt to bring that life into physical reality" Ayn Rand
Sorry, but wrong (to quote a cartoon I recently saw). There was no molecular oxygen in our atmosphere, you're bang on. But that was GOOD for life. Oxygen is lethal to a lot of life, and was lethal to most organisms that have ever existed on Earth. The oxygen in our atmosphere only built up about 2 billion years ago. At that time, a lot of organisms would have perished. We're just decendent form the ones that adapted. But oxygen is by no means necessary for life. Lack of it is probably more helpful than harmful, since oxygen tends to react with organic molecules to their detrement.
As for water... dead wrong. You'd do well to do a bit of research on that point. The early Earth would have had to have had water. Not having molecular oxygen in our atmosphere has nothing to do with having or not having water. After all, we have all kinds of oxygen in our rocks: it's the singly most abundant element in the crust.
Oddly, I was just having an argument with the head of CU's astrobiology institude about this point. Fits to surface spectra are seldom unique. It's a pain in the butt, be we can't even identify the minerals on Mars uniquely some of the time. Europa is worse. Not only do we not know the chemistry as well (rocks is rocks, and we have plenty of those on Earth), but the conditions are hard to reproduce. Temperatures of around 100 K, almost no surface pressure and a harsh radiation environment.
If you do a little digging (check back issues of Science magazine), you'll notice that there are already two theories about the mysterious absorber on Europa. There's McCord's salts theory and there's the sulfuric acid theory (put forward by Carlson). We can't distinguish between them right now. Adding another potential absorber to the fray doesn't really fundementally alter that we just can't tell right now what's down there.
In case you didn't get my point, 50 years ago scientists knew that there could be no life under such extreme environments as those surrounding Black Smokers, now we not only know better, it is likely that life started there. "Common knowledge" is not a good basis for science.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
that's just it - we *don't* know that there isn't DNA scattered out there in the interstellar void, like McDonalds wrappers next to a highway. We might go to Mars and find blooms of life all over the planet... might find it on the Moon. Hell, Jupiter could be raining down thousands of tons of organtic, replicating lifeforms in it's atmosphere. There could be life on every major body in the system.
Or there could be life on only one. We don't *know*. We haven't been there - we've only tossed low resolution (but well calibrated) cameras to fly past them at high speeds, and landed in a few of the most boring spots we could find on our own moon. Other than that, we sent a few landers to Mars and Venus, which didn't do much either.
And as far as even *organized* life goes, we don't know that much - we can be pretty sure of Mars due to the landers, and a few without any atmosphere... but in the oceans of Europa, the atmosphere of all the gas giants...
I'm not going to tell you that there *is* life there... but I defy you to show me that it *isn't* there. The dataset is insufficient to predict the most likely scenero.
As intelligent organisms, we cannot accurately calculate the probability of life being spontaneously created because we have never done it ourselves, EVER.
Got news for ya, pal - there's plenty of stuff we can watch every day that we can't do. That dosen't mean it dosen't happen. We've only been writing it down for about 6000 years, and keeping decent records for the past few hundred. We don't even know how *we* arose, when or where. And from fossil records, it looks like life has risen and fallen on our own planet many many times (and I'm talking "make it to the multicelled stage, and then fall back", not dinosaurs - they are our brothers in comparison). Once complex lifeforms (and sex) caught on, life got really diverse and really pervasive on this planet. If that didn't happen, Earth would look much like - well, what we can see of the other planets and major moons.
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Evan
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
No, because we do not know that life first formed on Earth - the "space seeding" concept grows more likely when you consider that ALH 84001, while it can not be shown to have definitively brought life from Mars, is pretty accepted to have been *capable* of doing so. Life, being small replicating units, is quite capable of having strewn itself across space. Who knows - maybe this area of space is covered in DNAish life, and other areas have other forms of replicating instruction sets - possibly in other phases of matter.
if we can find the probability of an event in a domain, and have no evidence to the contrary for other domains, Occam's Razor would dictate that this probability also holds for other domains.
Look at the domain we do have. Earth is covered in life. By your logic, every other unexplored domain would be similar. Certainly by your logic, the *existing* item that demonstrates the phenomina would be more likely than the theoretical one, right? The salts are theoretical, whereas multiple examples of bacteria exist, which *also* satisfy both the visible color and color distribution.
But *I'm* not saying it's life (note that I make this clarification in each post) - I am saying that one can *not* derive the necessary probabilites from our observation to date. We have one planet that we know details about, and extrapolating from that one planet is idiotic, whether you use that extrapolation to say "there's got to be life everywhere" or "We're not pulling in Martian HBO, so there's no life out there". The other bodies in the system are radically different, more extreme than the most extreme conditions on our planet. We have no idea what chemical reactions occur in some of the conditions that exist out there, let alone what *is* out there.
Years ago, they thought the seafloor was a dead zone. Then they found it was covered with oases of life (and yes, I looked that plural up). The point is not that life was there, but that, given all that we knew about life, it "couldn't logically have been", and it was. Now you say that Europa "can't logically have" life. You don't know, and have absolutely *no* detailed observations of any other planet than Earth, and thus cannot extrapolate. Occam's Razor cannot work when we don't *know* what the most simple explaination is - we don't know what is common even in our own solar system.
We HAVE NOT created a mixture of salts that match this signature. This does not mean that doing so is impossible or even improbable for us. We've only had the data a short time, and there are more than a few combinations to try to figure out what a correct salt would be to produce such a spectral signature. There may have been no reason to create such salts in the past.
We HAVE NOT created a mixture of chemicals that create life. This does not mean that doing so is impossible or even improbable for us. We've only had the data a short time (Since Watson and Crick figured it out on February 28, 1953 - we've known about fusion prior to 1938), and there are more than a few combinations to try to figure out what a correct reaction would be to produce such a structure as DNA. There may have been no reason to create such chemicals in the past.
And we have already created simple chemicals that reproduce given raw materials - DNA is more complex, but not impossibly so. If, tomorrow, someone created DNA in a lab, would you say that there might be life on Europa? What difference would it make? Absoluetly none. The current capabilities of human technology does not define what the universe is capable of containing. Do not confuse technology with science.
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Evan
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien