Domain: astrobiology.com
Stories and comments across the archive that link to astrobiology.com.
Comments · 19
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The toilets of the Gods
Perhaps the great author Arthur C. Clarke was not far off in his hypothesis.
Being descendants of... alien poo... is a humbling thought.
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Re:Capable of supporting life?
Considering the top limit for hyperthermophiles here on Earth is 250 degrees F, it's not just human life that couldn't survive there. If we're going to assume it's life unlike anything we've ever seen before, then why do you think the presence of water or CO2 will help?
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Re:Yet more proof...
I would disagree. Life, or at least life that we could recognise as life, would have to start on planets with the right conditions, i.e. Earth-like.
So this isn't life? The conditions in which many of these organisms live are extremely rare on Earth and extremely common on other planets, or even meteorites.
I propose that in fact, humanoid life is probably more likely than people would expect.
Nice scientific statement there "probably more likely than people would expect". How much is that in Volkswagens?
By your own previous statement (which I disagree with, but you obviosuly don't), life requires an Earth-like planet. Since the number of known Earth-like planets is one, life (humanoid or otherwise) is, by your reasoning, extremely unlikely.
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Re:Very careful--only one chance
bacteria has definitely proven itself here on earth, living in the most extreme conditions across a wide spectrum of environments that vary in temperature, pressure, and exposure to light and food sources.See Life in Extreme Environments
Its not beyond reason to think they couldn't live in an environment like the moon. Perhaps we could use some creative genetics to make *helpful* bacteria that can live in this environment. -
Re:The other big breaking news...
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Re:Study hot life instead
Life exisiting in enviroments we consider extreem is not unlikely. While it is true that extreem cold may slow evolution due to the slower life processes that may be insignificant if the life form has been around long enough.
Here is an interesting linke on Extremophiles...
http://www.astrobiology.com/adastra/extremophiles. html
Enjoy. -
I wonder...
Suppose there is intelligent life in there, what will they think of earth creatures?
"Amazing! The third planet creatures support temperatures so high that none of the titan lifeforms could withstand. Let's call them extremophiles".
Kinda makes you think... -
Wrong again....
It was Natural selection the whole time.
The process is geared to produce things that are: a) Hardier and better equipped at survival, b) better equiped to reproduce themselves in the environment.
This applies to the basic chemical components and the proteins and the organisms and the etc. The more stable and reproductive a system is the more of them there are likely to be for a longer period of time. The End.
Read about RNA, it's ability to reproduce in small strands and the abiotic clay-catalyzed synthesis of RNA. Here is one link of the thousands available online: http://www.astrobiology.com/asc2002/abstract.html? ascid=214
And here are that other thousand (actually 21,600) I was mentioning: http://www.google.com/search?sourceid=mozclient&ie =utf-8&oe=utf-8&q=clay+synthesis+of+RNA -
Re:The importance of voting 3rd party is to be seeHave you read the Libertarian party platform on the environment?
Actually, yes. To put it bluntly, the measures the currenly stated pricinples allow, such as as described in the platform, appear utterly inadequate.
As an single example, the impact that XYZ-Corp's completely unfiltered coal burning plant has only a de minimus impact on the breathability of the air over the 1.1 acre my last house was on. The platform seems to suggest that the laws should be altered allow me recompense or cleanup assistance. However, this neglects marginal cost of enforcement actions: to wit, the cost of my proving that it was XYZ-Corp's plant contributing to the unbreathability of my air, the time and resources that XYZ-Co spends on proving that coal ash is perfectly safe, and the time of the judge and lawyers spent arguing over this drivel. These non-zero costs largely act mostly as "friction" losses in the economic system.
Assuming that the public trust is not betrayed by politicians in power, the economies of scale provided by the fiction of "public property" make enforcement economically practical. There are obviously lots of other similar examples besides XYZ-corp. Libertarians far too often appear to ignore these economies of scale, the informational cost in economic transactions, the imperfect utility value of money and the existance of non-commesurables, the number of assholes already clogging our courts and spam-filters, and a number of historical hazards like abusive monopolies.
Furthermore, in a longer term view, I see very little in the current libertarian principles that encourage maintaining biodiversity, which is essential to making an ecosubsystem (EG, life on land) resiliant under climatalogical shifts-- which occur naturally even without human greenhouse intervention. Now, these shifts by themselves are unlikely to wipe out all life on earth, but it could easily remove the nitche for 50-100 kilo bipedal large-skulled mammals which (most days) I would find a Bad Thing.
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Re:Cover Your Nose
You can definitely not rule the chance of some unknown volcano or thermal source down there, inspite of the ice over the surface
Who knows, may be some organisms are out there surviving on the very little heat from the earth's core (that's a little too imaginative but you can't say it's impossible)
Check this out for Life in extreme environments
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Re:The trouble with isolated environments
Io?
It's highly unlikely that there's any life on Io. It appears to be too extreme for extremophiles. Perhaps you are thinking of Europa. Europa's the icy moon. Io's the volcanic one covered in sulfur. -
They did this in Antarctica
This is interesting because our lecturer at McGill just finished telling us about how they did this in Antarctica 10 years ago. The success of that mission in proving that life exists under 3 metre ice sheets (on lakes) in the McMurdo Dry Valleys is one of the reasons why this mission to Europa is planned. Great pictures of my lecturer (Andersen) in Antarctica are here. The video footage is again even more impressive - whole unadulterated sea beds of stromatolites and other cyanobacteria like nowhere else on earth.
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You joke but terraforming is a good idea
Let the terraforming begin!
You may be joking but I think it's a good idea. I think the odds of finding life on mars is slim to nil. Right now they are fruitlessly running around hoping to find past traces of life.
Terraforming will be a long long process. I say we jump start it by tossing out some extremophile microbes and see what takes root. Scatter them around the water laden edges of the poles. Anything that produces organic compounds has got to be better than what Mars has now.
At this point we have some clue as to what kind of compounds and weather conditions exist on Mars. Let's set up some test beds here, genetically reengineer existing extremophiles and see if we can get something that grows. -
Re:Fermi's paradox?
Ahhh, but to believe Fermi's paradox, don't you also have to believe that we will never travel "seemingly" faster than light, and that we already aren't being visited by intelligent life?
Both of which I do not subscribe to.
Some others who may disagree with Fermi.
And for those that wish to toy with probability:
Universe is approx. 12.5 billions years old
our little planet is approx. 4.5 - 5 billions years old, relatively young
and humans have been on this planet for only approx. 200,000 years, far less time than the dinosaurs were around (150 million years compared to human's measly 200 thou). And yet, in that time we have put one of our kind on the moon.
We humans have been around for approx. 0.000016% of the age of the Universe.
Extremophiles: Life arises much easier than previously thought and the idea of life needing Earthlike conditions is quicly being proven false.
Extrasolar planets:
Current numbers show that there should be approx. 100 billion extrasolar planets in this galaxy alone. There are 100 billion galaxies.
All I'm saying is that the simple probability of intelligent life is gaining ground through the ongoing discovery of human knowledge about the universe we reside. -
Re:How ridiculous,
However, AFAIK bacteria found living deep in the arctic ice isn't doing much living. It's just there doing nothing until it thaws and it's certainly not actively evolving. Please correct me if I'm wrong
One of the largest lakes on earth lies 4km below the arctic ice sheet. It is about 10,000 square km and nearly a half kilometer deep at places. Biologists believe that because the lake has been cut off from the rest of the planet for 15 million years or more - well before the human race evolved - microbial life in the lake could have quietly been evolving into strange and unique forms.
And even activity in frozen ice: observations have revealed the presence of active cells in the coldest ice horizons (-20C)
There are all sorts of energy sources and gradients. The fundamental requirement for life to appear is for there to exists a sufficently complex system. Just because all life we know of is based on carbon chain molecules does not mean that that is the only complex system capable of yeilding life.
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If life is on Mars...
...it would probably exist as single-celled forms such as bacteria, cyanobacteria,
and fungi found on Earth. The most interesting thing, though, is that the
origin of such a Mars life form could probably not be Mars-based. On
Earth, we have mightily strained to hypothesize an origin of life in primordial
ocean soups and atmospheres
in the presence of electric sparks and self-assembling
molecules. These theories have been severely weakened
in recent years with the discovery of fossilized life forms on Earth with
an apparent age of 3.5+ billion years which, given the estimated age of the
Earth, would imply a much more rapid creation of life than the hypothesized
mechanisms would allow. If life is present on Mars, the Earth-origin
theories of life are weakened even further, in the absence of evidence for
the necessary atmospheres and oceans on Mars, and theories for extraterrestrial
origins of life would gain traction.
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Correction: The real story
Once again Whitehouse jumps to conclusions. He calls this yet to be announced discovery "Ice oceans". This is a slight exageration. He got his information from a story on SpaceRef, one that is a bit more accurate and which was posted on May 22. It does seem from preliminary results, that will be announced this Thursday, that a great deal of water ice exists under the Martian poles.
Dr. Whitehouse is the same guy who at the beginning of April read an abstract for the NASA Astrobiology conference and concluded the author had found life on Mars! He then reported this on the same BBC web site. He was ridiculed for this. If you want the real science scoop I suggest you look to other sources such as SpaceRef and not the BBC in the future. -
Re:Scientific press releasesThis is an abstract of a poster that Dr. Stoker is presenting Search for Spectral Signatures of Life at the Pathfinder Landing Site at the Astrobiology Conference next week - presumably sent in a while ago.
The Superpan, an image product from the Pathfinder lander camera, is a multispectral panorama of the Pathfinder landing site acquired in 15 wavelengths in the spectral range 440 - 1100 nm. We have performed an automated search of the Superpan image cubes for the spectral signature associated with chlorophyll. First, images were calibrated to radiance values and then the multispectral images were co-registered to subpixel accuracy. An automated pixel-to-pixel search was performed on a 3-filter set of images (530 nm, 670 nm, 980 nm) to identify pixels where the following condition was met: 530 nm > 670 nm, and 980nm > 670 nm. Thus, we searched for the spectral signature associated with red light absorption by chlorophyll. When this case was met by the search routine, we plotted a full spectrum for the involved pixels and carefully examined the images. The condition was met for small areas in six image cases. All of these cases occur in near field images, where resolution is highest. Four of the cases occur on the spacecraft and appear to be associated with spacecraft structure. Two intriguing cases occur in small areas on the ground near the spacecraft.
So it was an abstract, not a press release. And partially cmpleted studis are certainly fair game for a scientific meeting. But, if it is not ready for publicaton in a scientific journal, than why is it ready for the popular press? Obviously Dr. Stoker's call
... granted, getting BBC-caliber press is tough to turn down. -
nutty bacteria
well there's a bateria(D. radiodurans) that can survive the levels of rad's that you get when you drop a nuke,
somthing like 1.5 million rads..
heres a good link with lots of other nutty bugs
i'm sure a few of them could survive anything that space d the sun can throw at them.