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vimy

What would we do if an asteroid was on a collision course? Nuke it? Can ICBMs even go to into space?

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Redirect it. Double Asteroid Redirection Test mission is going to test soon if this would work in practice:

https://en.m.wikipedia.org/wiki/Double_Asteroid_Redirection_...

I’ve got no experience with this stuff. Is it possible to model asteroid redirection in KSP or something similar?

One oddball idea I wonder about is turning suitable asteroids into something like an O’Neil cylinder. They offer lots of mass that you don’t need to haul up and could be resourceful. Seems the mass would help with radiation hazards. Gravity could be simulated by spinning them through traditional means. I’m talking about hollowing them out.

There is even a KSP tutorial for asteroid redirection. Stock game is designed with task in mind.

>Is it possible to model asteroid redirection in KSP or something similar?

Yes, you can do it in KSP.

Thanks that's interesting. The article says 0.5mm/s of change is enough to miss the earth, but how much time ahead do we need to find the asteroid? (Assuming we launch the day we find the asteroid, which is politically-wise unlikely but well)

So with an end-stage interaction where you're not considering keyhole effects, you very roughly you need to accumulate an Earth diameter of position change. So Earth diameter is ~13000km, so that works out 26 billion seconds or 825 years.

So in real terms, we'd probably wanna do a but more delta V than that. At 1cm/s, you're down to 41 years for example.

Doesn't this assume the asteroid is dead center targeting earth?

Good point! Assuming that the asteroid sees Earth as a disk that it can hit anywhere uniformly at random and also that I can still do calculus in my head, looks like the expected radius away from the circumference is only 1/3 R?

The Daily Tribune: "thank the heavens! Earth saved by Wikipedia article"

https://www.nasa.gov/planetarydefense/dart linked from the Wikipedia article

Trivialize the threat publicly, buy/sell off all relevant stocks, then announce threat is worse than anticipated.

Deny again that asteroid is a threat. Redraw a different course in red sharpie over the actual trajectory showing a path missing earth.

Discredit astronomy, discredit nasa, discredit physicists like there's no tomorrow.

Only if they were making money off the asteroid. There’d be more money to make in redirecting it. Especially if we’re talking 150+ years from now with much better space capacities.

This summarizes one possible scenario. https://twitter.com/mycoliza/status/1417539271192309761

We can only hope that said asteroid isn't too big and evacuate the area of impact. We can't do anything to prevent it. ICBMs can't even target something in space, and even if we blow the asteroid with one the same mass would still be flying towards earth as a shrapnel. Theoretically we can try shooting it with a laser to evaporate part of it creating thrust to divert it, but we don't have lasers that powerful and probably wouldn't. This is uncomfortable truth - we are completely defenseless against asteroids.

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