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by speeder 4823 days ago
Getting down is way easier than getting up.

ISS has some engines, crashing on earth is very simple, you can just thrust in the opposite direction that you are going (thus falling into the planet, although slowly and probably astronauts can find the attacker and put it back into orbit before anything serious happens) or you can trust in a diagonal of sorts, to slow your speed AND toward the planet (if you just accelerate toward the planet is more probably that you will only create a elongated orbit, and if you insist, you will slingshot out of orbit).
2 comments
redblacktree 4823 days ago
It seems like the harder part would be hitting New York. You could crash the ISS somewhere on Earth pretty trivially, if you had the controls.
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icambron 4823 days ago
Assuming they didn't, you know, disconnect you while you were doing it. There are actual people up there; presumably they have manual overrides.
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redblacktree 4823 days ago
Right. I was assuming/implying a lot by saying, "if you had the controls." In the hypothetical where you have complete control of the ISS (despite manual overrides, et al), you'd still have a very hard time hitting a specific target on Earth. You could crash the thing fairly easily though. That's all I meant to say; I understand that this isn't a practical reality.
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icambron 4823 days ago
Yup, I understood. I was just adding a thought about how it was even more impractical than your comment suggested. Wasn't arguing against your point itself.
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DoubleCluster 4823 days ago
I'm not sure the ISS has enough delta-v to get back down quickly. Lowering the orbit enough so that it will fall down in a few weeks is probably possible.
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lutusp 4823 days ago
It's likely that a decent orbital dynamics model and a relatively small, well-timed delta-v would bring the ISS down within a rater small planned impact area. It wouldn't be necessary to decelerate very much to accomplish that. Remember that the ISS must periodically boost its orbit to compensate for frictional losses, on that basis it can be assumed that the craft's dynamics are well-understood:

http://www.heavens-above.com/IssHeight.aspx

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