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Pieces of Ancient Earth May Be Hidden On the Moon
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.'"
It's a... oh, right.
Don't be too hard on yourself.
At least you got halfway there.
"I've got more toys than Teruhisa Kitahara."
Why the hell would you model an asteroid with some improbable shape like a cube?
Weaselmancer
rediculous.
Here's a good reason to go back to the moon if there ever was one. Or at the very least a better excuse than we've had so far.
Though the survival of the species is always a good reason...
All rites reversed 2010
Can just see the reaction to this. Life can't survive elsewhere in the solar system. It's all pieces of Earth that got blown out.
We're whalers on the Moon
We carry a harpoon
But there ain't no whales
So we tell tall tales
And sing our whaling tune
The Admin and the Engineer
Tax the little buggers up there!
Table-ized A.I.
I can confirm that there are pieces of the Earth in the moon. Somewhere in the back of my closet, I keep a fossil of a ancient platypus that astronauts brought down from the moon a few decades ago. Looks an awful lot like Hexley.
McCain/Palin '08. Now THAT's hope and change!
My granma's spectacles!
A cube is pretty much the worst shape possible when it comes to distributing the force of an impact evenly across the entire object
Not true; What about those crystalline spacecraft that the Kryptonians use to send their infants to Earth in? They have all sorts of jutting and produding suraces.
The wheel is turning, but the hamster is dead.
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.
Presumably the collision needed to splash a bit of rock off the Earth, through its atmosphere, up its gravity well to the moon would be at least 6 times as forceful as the collision with the moon.
They'd have to show that bits of organic material would survive both collisions to make it plausible.
Then explain how you would go looking for the few unlikely surviving chunks on something the size of the moon. Which by the way keeps getting hit all over with rocks from everywhere else, hence all the dust and craters.
Good luck with that.
Or is this just one of those things like string theory where you get to make up a hypothesis that you can't possibly actually falsify?
-- What do you need?
-- Gnus. Lots of Gnus.
The article doesn't mention how these earth-originated asteroids become space-borne, except a brief mention of the "Late Heavy Bombardment." I would think that pieces of earth that are sent into space by other asteroids hitting earth, would be subject to *far* more stress, heat, and general voilence in being struck hard enough to reach escape velocity, than they would on a simple re-entry.
Surely the impact event and associated energy required to eject the matter from Earth's stronger gravity and much thicker atmosphere, would be far worse when compared to the landing on the moon, no? (I know it's not a direct comparison, but consider how much fuel the Apollo missions in the massive boosters used to get out of Earth's gravity, versus how little they used to decelerate down to the moon's surface, carried on board the relatively small lander.)
Love many, trust a few, do harm to none.