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Earth Life Possibly Could Reach Titan
dylanduck writes "New simulations show that big asteroid impacts on Earth could have sent about 600 million boulders flying into space. About 100 have reached Jupiter's moon Europa - but they landed at 24 miles/sec. 'This must be rather frustrating if you're a bacterium that survived launch from Earth,' says a researcher. But 30 boulders from each impact reach Titan - and they land gently." From the article: "'I thought the Titan result was really surprising - how many would get there and how slowly they'd land,' Treiman told New Scientist. 'The thing I don't know about is if there are any bugs on Earth that would be happy living on Titan.' Titan's surface temperature is a very cold -179C and its chemistry is very different from Earth's."
Lawyers.
They can survive anywhere.
liqbase
Leads to the interesting possibility of xenophilic bacteria and algae impacting Jupiter and having their entry slowed greatly by the thick atmosphere. The deeper it goes, the warmer it gets, and there are bands in Jupiter's atmosphere that are comparable to Earth's atmosphere, past and present.
Might be interesting to one day discover man was far from the first Earth-borne species to begin colonizing other planets in the solar system.
"To pass through the jungle; silence, courtesy, ferocity, as the occasion demands." -- Kamau, "Proper Passage"
How about this:
Named the World's Toughest Bacterium by the Guinness Book of Records, the large red spheres of Deinococcus radiodurans (translation: strange berry that withstands radiation) can not only endure acute radiation doses of up to three million rads but more remarkably, can actually grow when exposed to radiation continuously.
You really don't want to meet this in a dark alley, however with that much radiation, I doubt it would be dark for long.
liqbase
Bacteria survived several years on the lens cap of a camera left on the moon. It's resilient stuff!
Does this sig remind you of Agatha Christie?
Tartigrades, otherwise known as Water Bears might survive such a journey. They're the cutest microscopic animals ever!
'This must be rather frustrating if you're a bacterium that survived launch from Earth'
On behalf of the League of Sentient One-Celled Organisms, I would like to assure you that it is nowhere near as frustrating as your high-handed, primitive, and anthropomorphic notions of bacterium emotion.
Actually in many of our cultures (and I use that term advisedly), being hurtled through a vacuum and smashing into a rock is considered to be a transcendent spiritual experience, and required as an initiation rite into our shamanic traditions.
Blow that into your Kleenex.
Ooo man the floppy drive is broken. No wait. The computer is just upside down.
At -179C, the bacteria are gonna need parkas.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
It looks like Earth's pecker tracks could be all over the solar system. What if Europa had an atmosphere early in it's life? Was it always relatively airless? So even if we discover life elsewhere in the solar system, there's a good chance it'll resemble Earth's. Even if Europa was airless what about this scenario? Big Earth rock hits Europa, vaporizes millions of tons of ice and creates a temporary atmosphere. Then a second rock hits Europa in this brief interlude. It could have survived. Unlikely, but possible.
"You'll get nothing, and you'll like it!"
"The whole thing was a simulated what-if, something made abundantly clear from start to finish. They "Know" these impacts happened and at precisely what speed because IT WAS A FEKKING SIMULATION, DAMN IT!"
This is true, but also stated in the article "The cause of such impacts would be comets or asteroids between 10 and 50 kilometres wide, Gladman told New Scientist: "The kind of thing that killed the dinosaurs."" meaning that these numbers were not just pulled out of an orifice but rather based on actual historical earth impacts. Is it proof that these rocks made it to Titan (and in the numbers estimated)? No. But it is probable. The last line of the article sums it up nicely; "Gladman agrees that life may be unlikely to survive once on Titan. But he says major impacts may have happened "tens of times" throughout Earth's history and that these could have sent Earth rocks to other solar system bodies. "I just set out to answer this question: is it possible to get something there?" he says. "The answer is yes."". Draw your conclusions from there.
Beware of he who would deny you access to information, for in his heart he dreams himself your master.
Solar Billiards - v1.3.11
Please input the following earth-impactor parameters for your simulation
Impactor diameter (m): 5000
Impactor velocity (m/s): 12000
Ecliptic Declination (deg): 7.3
Please input the following solar system parameters for your simulation
Target diameter (km): 4000
Target solar altitude (AU): 15
System asteroid density (objects/AU^3): 0
Click start to begin
Calculating Trajectories...Done
Results:
Total impacts of earth origin: 107
Impacts of non-earth origin: 0
Congratulations! Impact count greater than 100! Click here to redeem your free iPod!
Tough bugs, sure, but traveling through space also means withstanding the full bore radation of Mr. Sun, with no atmosphere to protect you. I'm not sure I want to meet one of these in a dark alley.
You probably already have. There are bacteria that can survive and even grow exposed to levels of radioactivity found in some parts of nuclear reactors. It looks like some of these bacteria also live in the human stomach.
The thing is, harsh environments and to things like drying out can cause DNA damage, and the same incredible repair mechanisms that help some species to survive those allow them to survive intense radiation.
Incidentally, bacteria surviving to reach Titan is not that interesting - far more exciting is the possibility of them reaching another moon of Saturn - Enceladus, which probably has liquid water.
Yikes, that's one helluva commute.
Maybe that explains why so many modern day humans don't seem to mind driving 2 hours each way to work every day. It's in our genes!
I read Usenet for the articles.
Wow, what a novel idea! I think we've got an awesome new theory here.
Let's give it a name. How about panspermia?
Or, you could just RTFA.
AC: Only on slashdot... could the sentence "My hovercraft is full of eels." be moderated "+4, Insightful
Well, as long as they had an intel processor with them, they've got plenty of heat to survive.
"Everything worth innovating today will go to court tomorrow."
I mean, if we ever got there and searched for native life forms, these findings would just add another factor of uncertainty. Say we send up robots or even taikonauts (probably won't be astronauts any way), and they really do find DNA/RNA-based life (except lawyers, as someone else suggested). How would one tell a archaebacterium which hitch-hiked the vessel from an archaebacterium that hitch-hiked an asteroid boulder from a bacterium that has been created there?
The grass is always greener on the other side of the light cone.
The fact that we have determined these things hit Earth makes them no more likely to hit Earth. I say we carry on ignoring them like we did before anyone had any clue such a thing could happen.
"The White House is not an intelligence-gathering agency," -- Scott McClellan, Whitehouse spokesman.
Ok this time we compromised! We converted the 40 km/s of the article into 24 miles/sec, but kept the -179C unconverted.
For our next science article we will do the opposite. When we think you are ready -- but only then -- we won't convert anything and you'll be on your own.
As far as life as we know it, there is no evidence that microorganisms could grow at -179C. There is some evidence that hardy spores can survive in extreme conditions (even naked space as is the case for some mold spores that briefly enter the upper atmosphere of Earth and come back down to spread long distance), but I find it difficult to believe that anything could grow and divide at such low temperatures. That seems chemically and thermodynamically impossible with the microorganisms that we know of now. The leaves the possibility of evolution to some type of life we don't know about, but again, evolution requires geological time scales, and the trip from here to Titan, presumably in a dormant state, would not allow sufficient time or for that or the multiple rounds of natural selection. Neat idea none-the-less, but not enough incidents to play the probability game properly.
>chemistry is very different from Earth's.
There are some Earth life forms with some pretty weird chemistry. One example is purple sulphur bacteria. Instead of using water as a reducing agent, they use hydrogen sulfide. This is oxidized to elemental sulphur and sometimes on to sulphuric acid. Heck with this water/oxygen thing. These are a very old group of organisms.Some mornings it's hardly worth chewing through the restraints to get out of bed.
Could there possible be bits of dinosaur DNA orbiting around in the deep freeze of the solar system? or would high energy particles quickly destroy the DNA? Well if anything sounds a like a great mechanism for a movie. Man finds chunks of frozen desiccated dinosaur. Man brings back Dino DNA to earth and splices DNA with that of frogs, Man recreates Dinosaur species, Dinosaur eats Man. Appologies to Ian Malcolm...
And the decelleration and temperature resulting from the crash landing is substantially different from the acceleration and temperature resulting from an explosion that caused the rock to exceed escape velocity in the first place?
Yep.
Not "the explosion" itself, but the environment felt by the launched rock, which could be lifted relatively gently by the rocks and soil under it, as the atmosphere above it is lifted out of the way / along with it by it and the neighboring material.
It isn't the stuff that gets HIT by the asteroid/comet/whatever that get's launched. It's the stuff on and near the top of the ground nearby that gets lifted by the violence spreading out below it.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Steven N. Severinghaus
...why shouldn't bacteria from Earth be able to grow on Titan? Microbes are amazingly hardy organisms, they can thrive as chemotrophs at the bottom of the ocean near volcanic vents or in other incredibly hot temperatures (one such microbe has an enzyme that lets biologists amplify DNA for legal and research purposes). If they can survive the extremes of air, ocean depth, and heat, why not those of cold and darkness?
As long as there is a Second Amendment, there will always be a First Amendment.
People are also only pointing out animals we know exist being on those boulders. It's entirely possible there were many more species hundreds of millions of years ago that were as resiliant as the "Water Bear" towards harsh conditions, but suffered some other short coming that lead to their extinction on Earth.
EpiAdv - if you like Pokey the Penguin, try this comic!
(Given that gigantic, green tentacled monsters haven't been stalking NASA bases recently, we can also assume that not only were they not killed off, they did not suffer significant mutation from the radiation. Actually, the study indicated that no obvious mutations had occured of any kind, implying that the DNA was highly resiliant to the effects of ionizing radiation.)
On the basis of Mir and the NASA experiment, it can reasonably be concluded that microbes can survive interplanetary travel, more-or-less intact, at least within the solar system. Deep space is far, far nastier and the present experiments don't show that interstellar microbial travel is possible... but it doesn't rule it out, either.
We believe that microbes can remain in a suspended state for tens of thousands of year (or perhaps millions), on the basis of studies of microbes discovered in ice core samples. It's not easy to rule out contamination, but the experiments seem repeatable. It is possible to imagine that microbes may be present in some geodes. They would certainly be present inside rocks that have fissures caused by flowing water or ice cracking.
Once you're talking of microbes on the inside of rock, then impact velocities would be much less important. The rock would absorb much of the impact, and the shattering of the rock would be a very useful way for the microbes to be released. In the case of interstellar travel, it would also provide better shielding. Ideally, you'd want rock from the Peak District in the UK - some places have a nice mix of galena (lead ore), calcite and blue feldspar. I could easily imagine a meteorite with such a mix containing microbes in amongst the calcite, and lead casing would improve the odds of surviving the millions - if not billions - of years needed to travel between systems.
(This is not to say this has happened, and I'm sure I'm going to get my wrist slapped by a geologist who will point out all the flaws in my reasoning. However, if in the year 3000 we finally reach Alpha Centauri and find a planetoid with bird flu on it, they'd better damn well name the planetoid after me.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Combine all this with being able to digest unconventional materials - your example was sulpher - and you've the makings of a beastie that would consider Titan the ultimate in luxury resorts.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
I saw a movie about that. Ripley escaped with the cat, but none of the other did. ;-)
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Deliberately contaminating the environments of our neighboring celestial objects with our mutagenic biomatter might be considered an unfriendly greeting by the local populations.
But we'll keep doing it anyway. It seems unlikely that human spacefaring will be found in the long term to be a significant vector for the spread of life -- not because we don't do it but because life has been littering the solar system for much longer than we've been exploring it.
In addition to the rocks that smote the dinosaurs which might have spread life to other planets there are:
The better question is not "does life exist elsewhere?" but rather "if not, why?" We just have to probe around as best we can to get some preliminary results on the first question before we explore the second.
The question I want answered involves the asteroids -- who will be the 49'er to figure out how to capitalize on that unimaginable wealth? The investment is significant, but if you could get a reasonable amount of water, a nuclear power plant and about 50 people to the asteroids, in thirty years you could own everything outside the moon's orbit. Of course at that point closing the deal on the rest of _everything_ would be trivial.
Help stamp out iliturcy.
Put a bitch in heat on Titan, and I guarantee a dog will stud Titan into being a giant kennel in no time. Life is incredibly persistent.
I scream. You scream. I assume that means we're both acquainted with the problem. We proceed.
Your comment advocates a
(x) theological (x) philosophical ( ) scientifictheory for life. Your theory is not acceptable. Here is why it's useless. (One or more of the following may apply)
( ) It has been proven to be inaccurate(x) It contains unprovable statements
( ) It doesn't propose any additions to knowledge
(x) It is not repeatable
( ) It can not be used to make predictions
(x) It purports to contain sufficient knowledge to live
Specifically, your theory fails to provide answers for
(x) When the universe first came into existence(x) How the universe started
(x) How long will the universe exist
(x) Why life began
( ) Where life began
( ) How life began
( ) When did life begin
( ) How did life start on earth
(x) When did life start on earth
(x) Can extraterrestrial life exist
(x) Does extraterrestrial life exist
( ) What happens when we die
(x) Can we create life
(x) 42.
and the following philosophical objections prevent it from being taken seriously:
(x) The work this theory is based on is hotly contested by its many proponents and your position is not clear.(x) This work is too vague to be useful
(x) This theory fails to acknowledge that the scientific method is constantly explaining acts previously attributed to gods
(x) Predictions made using this theory are usually wrong
(x) People who have supported this theory have also strongly denied theories now accepted as fact
Furthermore, this is what I think about you:
(x) Sorry dude, but you need to look up the definition of 'knowledge'.( ) This is a stupid idea, and you're a stupid person for suggesting it.
"Is it just me, or does the idea of meteors kicking stuff *off the earth* not pass the laugh test?"
Only a tiny fraction of the original mass need reach escape velocity to allow bacteria to escape (they're fairly small compared to some of these objects after all). If the moon formed from ejecta from a large impact (as seems to be the case), is it so hard to believe that objects a tiny fraction of that size reached escape volocity?
I rarely criticize things I don't care about.
No, because helium is a noble gas, and as such chemically inert. The reason oxygen is so usefull is that it is very highly reactive; while it is certainly possible for an organism to inhale helium and not be harmed by it - indeed, even a human can survive that - it won't do it any good either.
Waters role is as a small-moleculed polarized liquid. Since water molecules are polarized, there's a strong attractive force between them, giving water very usefull properties - surface tension, high boiling point, etc.
What, didn't you get the memo ?-)
I suppose it would be possible to build life from anything that can form complex enough structures, but would we recognize it as life is another matter.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
Oxygen is the simplest substance around that has those characteristics.
But couldn't life evolve to, say, breathe helium and drink alkaline, for instance?
Definitely no on the first one. Helium has no chemical properties whatsoever. Hydrogen isn't a good candidate either, since H2 is a reducer rather than an oxidizer. I would imagine that a cell that relied on an outside reducer would need to have free oxidizers sitting around inside itself. It would probably rip itself apart.
Drinking alkaline is more reasonable, depending on the concentration.
I don't know if there's a rule that says, "Anything in the universe that's alive has to breathe (carbon dioxide|oxygen), drink water, be carbon-based, etc."
The "carbon requirement" is simply this: only carbon can form large, stable, complex molecules. Sulfur and nitrogen can form polymers, but not complex ones. Silicon can form large complex molecules, but they tend to fall apart because of the availability of d-orbitals.
Human being (n.): A genetically human, genetically distinct, functioning organism.
You might be interested in D. radiodurans which can survive 1.5 million rads whereas 500 - 1,000 rads can kill a human. However this item explains the repair mechanism.
Bitter and proud of it.