Richard Fangnail wrote:
A fast-moving object like a meteorite compresses the air in front of
it, causing heat. Does an ordinary plane have a problem with this or
is it not moving fast enough?

Others have confirmed that supersonic aircraft need to have an allowance for
expansion built into their designs. Passenger airliners fly at speeds of c
400-500 mph and there is certainly some frictional heating.

The Siberian meteor of 1908 exploded in midair. Why do you suppose it
did, as opposed to hitting the earth?

It was moving at several km/sec and at that sort of speed, air resistance
generates a shockwave that will propagate through the rock/ice/whatever and
if the tensile strength is not great enough it will break up. I don't think
there was time for frictional heating to cause an explosion via ice
evaporation--the passage through the air lasted only a few seconds, and
heating propagates very slowly through rock.

If it was a stony object, like some asteroids that have been studied close
up, it may have had a fairly loose structure so it is not hard to see why it
would break up. I understand this is what is generally postulated.

In contrast, consider an iron meteorite, which would have held together.
They never found any indications of iron in the composition.

--
Mike Dworetsky

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