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0 pointsnradov3y ago0 comments

Doubt it. There's no way that lasers will be able to vaporize a huge asteroid. Realistic proposals for planetary defense call for intercepting asteroids very far from the planet and pushing them off course enough to barely miss us.

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lucubratory3y ago· 2 in thread

The point of the laser isn't to vaporise an entire asteroid. It's to push it off course enough to make it miss the Earth. The laser achieves that by pointing at a spot and turning that spot into an impromptu rocket engine.

nradovOP3y ago

An orbital laser won't have the range for that. The dispersion would be too high for any lens that we can practically launch into orbit.

More realistic proposals for planetary defense call for focusing on long range detection and then using a gravity tractor or a rocket motor landed on the asteroid to slowly nudge it off course.

lucubratory3y ago

I just don't think that's true. We launched Hubble and JWST, as well as many spy satellites with similar mirror size. If we're talking about lasers that could feasibly intercept ICBMs or hypersonics, that amount of laser power and a large lens should be able to exert significant pressure at range.

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