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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
Preliminary results show that all three species, the ordinary gut bacteria Escherichia coli, and extremophiles Deinococcus radiodurans and Sulfolobus shibatae, are just as good at explaining Europa's IR spectrum as the salts.
Except that the salt theory doesn't rely on extraterrestrial life being created on one moon completely inhospitable to life in the middle of nowhere.
Glenn Teeter from the Pacific Northwest National Laboratory in Washington state says bacteria aren't the simplest explanation for Europa's spectrum.
Yet...
No one has managed to come up with the perfect mix of [mineral] salts to explain all of Europa's spectrum.
Okay boys, settle down and apply a little common sense here. If the experiment works, let's ask ourselves why. At the least, it proves Europa has all the right elements (pun intended, for sure) for life to form.
Of course we still would want to go and see for ourselves, just to be sure. But let's make sure the astronauts pack lots of penicillin, just in case. {grin}
Do you like Japanese imports?
It's New Scientist. It sounds nice and could be a valid theory, but until we have more detail we won't know. This is what everyone wants to hear about Europa (because of it's oceans), but that doesn't mean that this is more than a guess.
See my previous rant. This seems to be yet another case where a writer for this news source has put their own sci-fi spin on what is otherwise a very unremarkable bit of information. Take five minutes to read and think about the points in this article, and you'll be sorry you did. It's chock full of conceptual holes, misunderstandings, and unfounded extrapolations into the news-bite realm of absurdity. Please stop posting this yellow journalism.
Steven N. Severinghaus
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
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.
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
We have failed to create sustainable fusion as well. Go out on a cloudless sky, and you will see as many arguments against your logic as there are stars in the... well, you get the idea. Just because *we* cannot do something doesn not mean it is not dirt common as far as the greater universe is concerned.
our past experience shows that it is easier for to generate salts that have unique properties than it is to create life
And yet we cannot create a mixure of salts to match this signature - the only thing that does exist that matches are bacteria. I would say that you are arguing for the opposition.
I should never consider that the probability of something that has never been observed should be considered astronomically low?
Something that has never been observed in a domain that has never had more than casual observation. If I tell you that there is a set of 10,000 numbers, and one is 89.63, what can you predict of the set? We know what color Europa is (in a few different spectra), and what it's surface looks like on a very low resolution - the kind of resolution that would miss life on Earth. That's it.
Given our current estimate of the probability of the formation of life, and our guess of the age and size of the universe, the odds that life would already exist are incalculably high.
And you would argue statistics with me? You are accepting probabilities that are utter guesses. Until the past few years, we had not even known if there were any other solar systems with planets. How can you propose the probability of something when you have no idea of the basic postulates to form an opinionated guess upon? Ask a dozen different scientists what the probability of life elsewhere in the universe is, and most will couch it in very measured words - the data is just not available.
I believe we must have been created.
A pointless statement in this debate - faith is not in question here (and a belief based on insufficient data is one founded on faith). What is in question is the relative probability that life is on Europa. I merely state that we do not yet know how common life *is*, and thus cannot predict the most simple answer.
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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