Re:How to destroy the Earth (completely)
by stcredzero on Monday June 21, 2010 @08:46AM
(#1448616)
Heating the biosphere and the crust to a depth of 5 miles to 500 degrees and keeping it there for at least a couple of hours would likely do it, even for the Water Bears and radiolarens. That could be accomplished with asteroid/comet bombardment. The energy budget for that is many orders of magnitude smaller than most of the proposals in the article.
Well you'd probably want to go deeper than 5 miles to be sure. But a massive comet strike doesn't guarantee the sterilization of ejected material which is really the difficult part. Because there is life that can handle vacuum you have to not only heat the world to 200C (we think) but you have do it in a way that nothing larger than individuals molecules escape due to heating. which is also tricky because at some altitude in the atmosphere evaporative cooling might allow for something to survive indefinite periods of superheated crust.
EDIT: really what it comes down to is how many 9s of biocide do you want. Ramming Luna into the Earth might accomplish 7 or 8 9s, but if you want to kill everything, 100% of life from LEO down not just practically everything it's going to take more finesse than that.
Re:How to destroy the Earth (completely)
by stcredzero on Monday June 21, 2010 @10:04AM
(#1448803)
Heating the biosphere by using a large cloud of orbital mirrors and inducing runaway greenhouse might accomplish your goal of 100% containment and sterilization, but if a few mites and microorganisms escape, that's close enough for me.
slacker
Re:How to destroy the Earth (completely)
by stcredzero on Monday June 21, 2010 @12:09PM
(#1449196)
It's called GTD. Getting Things Destroyed!
In that vein I'd like to say that killing all life currently within 6500 kilometers of the Earth's center of mass is, in some ways, harder than simply destroying the Earth.
Take for instance the humble Water Bear they range from microscopic to a millimeter in size and can survive being frozen to within a degree of 0k and have survived 10 days in hard vacuum, during which time eggs were laid and hatched. It seems likely that any of the various "disassemble Earth" methods would fail to kill them. Similarly any chunk of Earth with a sealed ecosystem, like some caves, might continue to keep going indefinitely.
Killing everything might require vaporizing the planet in the sun or eating it with a black hole.