@cstross That's assuming the dinos have nukes, of course. But there are a whole slew of advantages to nukes on this scale. They scale up REAL WELL due to the constant cost of the expensive fission primary and the cheapness of lithium deuteride.
And most of the "propellant" comes from the asteroid itself, as large swathes of the surface get vaporized with each nuke.
And you don't need to waste propellant matching velocities with the asteroid ...
@isaackuo @cstross FWIW, these guys argue a short-notice Chixculub class impactor could be pulverized with nukes, such that the majority misses earth. There's obviously a lot of uh… implementation details, but the basic argument that current tech could deliver the required amount of energy seems plausible
https://arxiv.org/abs/2201.10663
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