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by sholladay 15 days ago
Do you not consider Tunguska an explosion? It’s always described as such. IIRC, it never even hit the ground. Sure, a lot of the damage was caused by the air being compressed from above, but it created an air burst, which would have released a lot of energy in every direction.
1 comments
jojobas 15 days ago
No, it's a misnomer as with any other meteor.

If you were to witness the breakup from the bolide's reference frame and without all the rushing air you'd never call it an explosion.

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margalabargala 14 days ago
> and without all the rushing air

That's the exploding bit though. You don't need containment, you just need the the airburst. A hyper-heated pocket of air that then expands rapidly is itself an explosion.

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jojobas 14 days ago
>then expands rapidly

Except it doesn't. The breakup has roughly the same dynamics as dirt spreading as it gets out of a tip truck. The shockwave is not produced by the outward motion, it barely has any speed.

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margalabargala 14 days ago
You're conflating the outward motion of the rock with the outward motion of the air.

The shockwave is traveling at the speed of sound.

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