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I agree that detection is a very helpful first step and almost enough on its own. But I'm unsure how far this can be pushed-- I think impact certainty for a cen

I agree that detection is a very helpful first step and almost enough on its own. But I'm unsure how far this can be pushed-- I think impact certainty for a century or more might be physically impossible, because of uncertainty in orbital parameters and chaotic behavior of the whole system. I also believe the approximate bounds we have on impact probability are good enough for this estimate and quite unlikely to be off by a factor of 100, because we can guess at both size distribution and impact likelihood from craters (on earth and moon), and if the >10km object impact likelihood was over 1/million years we would expect to see a hundred times more craters of the corresponding size...

cogman10 1y ago
> I think impact certainty for a century or more might be physically impossible, because of uncertainty in orbital parameters and chaotic behavior of the whole system. We already have 10s of years of certainty with the current observations. Most of the uncertainty comes from the interactions of unknown objects. As the mappings of objects increase, our predictions will become much better. The other thing to consider is that large objects will have much better certainty. A 10km asteroid won't be influenced (much) by colliding with 100 1m asteroids. It will only be impacted if it hits or swings by something like a 1km asteroid. Rubin should in a pretty short timeframe (a few years) give us an orbital mapping of all the >1km asteroids, which is pretty exciting.