I appreciate the effort to put some numbers into this Fermi format! I’m not sure whether you intend the numbers, or the result, to represent your beliefs about the relative risks and benefits of this program. If they are representative, then I have a couple points to make.
I’m surprised you think there’s a 10% chance that an actor who wants to destroy the Earth this century will have asteroid deflection within their technological capabilities. I’d assign this closer to a 1/1000 probability. The DART mission cost $324.5 million, was carried out by the world’s economic and technological superpower, and its team page lists hundreds of names, all of whom I am sure are highly-qualified experts in one thing or another.
Maybe North Korea could get there, and want to use this as a second-strike alternative if they can’t successfully develop a nuclear program? But we’re spying on them like mad and I fully expect the required testing to make such a weapon work would receive the same harsh sanctions as their other military efforts.
I’d downweight the likelihood that asteroid deflection is their easiest method for doing so due to the difficulty with precision targeting from 1⁄7 to 1/1000. An asteroid of the size targeted by DART would take out hundreds of square miles (New York is 302 square miles, Earth’s surface area is 197 million square miles). Targeting a high-population area puts even steeper demands on precision targeting and greater opportunity to mitigate damage by deflection to a lower-impact zone. It seems to me there are much easier ways for a terrorist to take out New York City than asteroid deflection.
Since your estimates for the two scenarios are only off by 3 OOMs, I think that these form the crux of our disagreement. I also note that this Fermi estimate no doubt has several conceptual shortcomings, and it would probably be useful to come up with an improved way to structure it.
I appreciate the effort to put some numbers into this Fermi format! I’m not sure whether you intend the numbers, or the result, to represent your beliefs about the relative risks and benefits of this program.
Those are meant to be my actual (possibly unstable) beliefs. With the very important caveats that a) this is not a field I’ve thought about much at all and b) the numbers are entirely pulled from intuition, not even very simple models or basic online research.
I appreciate the effort to put some numbers into this Fermi format! I’m not sure whether you intend the numbers, or the result, to represent your beliefs about the relative risks and benefits of this program. If they are representative, then I have a couple points to make.
I’m surprised you think there’s a 10% chance that an actor who wants to destroy the Earth this century will have asteroid deflection within their technological capabilities. I’d assign this closer to a 1/1000 probability. The DART mission cost $324.5 million, was carried out by the world’s economic and technological superpower, and its team page lists hundreds of names, all of whom I am sure are highly-qualified experts in one thing or another.
Maybe North Korea could get there, and want to use this as a second-strike alternative if they can’t successfully develop a nuclear program? But we’re spying on them like mad and I fully expect the required testing to make such a weapon work would receive the same harsh sanctions as their other military efforts.
I’d downweight the likelihood that asteroid deflection is their easiest method for doing so due to the difficulty with precision targeting from 1⁄7 to 1/1000. An asteroid of the size targeted by DART would take out hundreds of square miles (New York is 302 square miles, Earth’s surface area is 197 million square miles). Targeting a high-population area puts even steeper demands on precision targeting and greater opportunity to mitigate damage by deflection to a lower-impact zone. It seems to me there are much easier ways for a terrorist to take out New York City than asteroid deflection.
Since your estimates for the two scenarios are only off by 3 OOMs, I think that these form the crux of our disagreement. I also note that this Fermi estimate no doubt has several conceptual shortcomings, and it would probably be useful to come up with an improved way to structure it.
Thanks for the engagement! Re:
Those are meant to be my actual (possibly unstable) beliefs. With the very important caveats that a) this is not a field I’ve thought about much at all and b) the numbers are entirely pulled from intuition, not even very simple models or basic online research.
Same :D