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Comment by Klathmon | Hacker News Reader

One really cool thing I heard in this video, is the double sonic booms from each booster.

There are reasons behind it that I don't really understand, but each booster makes 2 distinct sonic booms as it comes in to land. With Falcon Heavy launches, it makes a total of 4 of them!

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SmarterEveryDay has a great video explaining this audio phenomenon from a previous Falcon Heavy launch: https://youtube.com/watch?v=ImoQqNyRL8Y

https://www.spaceflightinsider.com/organizations/space-explo...

I don’t understand either, but read that supersonic objects generate shockwaves at nose, root of wings(if any), and tail. Shockwaves also may reflect off terrains.

Possibly it should always be “BAbababang-baaaang…”, and the first three might be either indistinguishable or ones after the first are too weak, except it becomes noticeably apart on extremely long objects like F9?

1: https://www.nasa.gov/centers/armstrong/multimedia/imagegalle...

In this case the two booms come from the "nose" (the engines, since at this point the booster is flying backwards) and from the grid fins at the far end. Given that the Falcon 9 boosters are about 70m tall, that would mean about a fifth of a second delay between the two booms when the booster is traveling at Mach 1.

As a kid I used to watch the Space Shuttle come in for landing, and it always had a distinct triple-boom on entry. Someone said it was the body and wing tips each making their own boom, but I never really confirmed it.

IIRC it was shocks at nose, wing tips and tail.

The booms are probably from the bottom and then the grid fins.

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