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by dabluecaboose 1117 days ago
> There would be no atmospheric scattering

Kind of by definition if something is -sonic then it's in the atmosphere. There would be less scattering but there would definitely be some on the target end.

1 comments

The article said ICBMs were hypersonic, and those certainly spend a lot of time outside of the atmosphere.

The gliders seem to spend the entirety of their trip in the upper atmosphere, though.

Reentry does kind of by definition enter the hypersonic regime, but it's somewhat unintuitive to the layperson since Mach 5 is much slower at those very low pressures, and it's an entirely different beast than flying at Mach 5 in-atmosphere proper