Pieces of Ancient Earth May Be Hidden On the Moon 96
swestcott brings us a story from Space.com about the possibility of finding evidence for ancient Earth life on the moon. A team of scientists has published work confirming that meteorites originating from Earth could have remained sufficiently intact while colliding with the moon to allow the survival of biological evidence for life. Quoting:
"Crawford and Baldwin's group simulated their meteors as cubes, and calculated pressures at 500 points on the surface of the cube as it impacted the lunar surface at a wide range of impact angles and velocities. In the most extreme case they tested (vertical impact at a speed of some 11,180 mph, or 5 kilometers per second), Crawford reports that 'some portions' of the simulated meteorite would have melted, but 'the bulk of the projectile, and especially the trailing half, was subjected to much lower pressures.'"
Re:Molten Planet Sends First Life To Moon! (Score:3, Informative)
Did you know DNA is what makes a lot of the choices in your brain? Right, in every neuron, every time it fires, messages go into the nucleus (that's the dna's housing and equipment) and get translated by RNA and DNA... the resulting parts of the neuron that fire are due to the response from the DNA!
Erm... not really, no. Most "firing" of neurons (generation of action potential) happens on a purely electrical basis. There is chemical modulation of this based on quantities of neurotransmitters that are produced by the nucleus, but this only takes place on a very long term scale (think minutes, not the milliseconds it takes for an action potential to propogate).
Besides, so what if it does? DNA is responsible for governing _every reaction that goes on in our body_ by determining what new substances are to be produced based on the quantities present of other substances. That's simply how life works.
We use this same thing to make RNA computers that can do massive calculations in a fraction of the time it would take our current PCs to do it (well, the setup takes a while, yuk yuk.) This building blocks of life, which came about in a cave as the world cooled off from its volcanic eruptions, just randomly have supercomputing ability?!
The stimulus/response mechanism provided by RNA is an important part of life because it allows it to rapidly adapt to changing circumstances. But (1) it isn't really a "supercomputing ability". At least not until a lot of it has accumulated in the same place. Early RNA was probably extremely simple compared to what we see today. And (2) it didn't have to occur randomly in a form anything like as complex as RNA. Current theories of the origin of life include a few alternatives, including a much simpler system called PNA that might have evolved into RNA, and the possibility of "metabolism-first" abiogenesis which allows for a self-perpetuating cycle to exist and evolve without the complexity of a self-replicating information store. It then evolves such a store and begins replicating.