Slashdot Mirror
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."
"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.
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.
Steven N. Severinghaus
There is certainly a broad layer where the pressure and temperature are roughly Earthlike. However, there is nowhere in Jupiter's atmosphere where the composition is more than vaguely similar to Earth's primal (prebiotic) atmosphere, and nowhere similar to Earth's current atmosphere at all. There is effectively no free oxygen in Jupiter's atmosphere, and only tiny traces of anything other than hydrogen and helium. Most of the traces are simple alkanes and water.
When all you have is a hammer, everything looks like a skull.
Ribosomes. If they are the same, or similar to one of the few types in earth-life, then it is almost impossible that they came from elsewhere. If they are different....
Laws are horrible moral guides, moral guides make even worse laws.
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
Actually, microbes are so tough that there is little need to absorb impact stresses. Some experiments have involved bacteria put inside a rifle bullet and fired at rock (to see if they could survive the decelerations of a meteor impact). The bacteria survived and could reproduce.
This is why there is little need, as this article suggests, to have the rocks containing bacteria travelling slowly.