Ten things you don’t know about the Earth
Destroying the Earth is hard
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Even giant collisions can’t vaporize the planet. An object roughly the size of Mars impacted the Earth more than 4.5 billion years ago, and the ejected debris formed the Moon (the rest of the collider merged with the Earth). But the Earth wasn’t vaporized. Even smacking a whole planet into another one doesn’t destroy them!
http://www.mazepath.com/uncleal/fourbomb.htm
There is another way to do it that is entirely straightforward – with a Styrofoam physical model no less. Oh, DARPA…