[meteorite-list] Speed that meteors enter dark flight?

[Graham Ensor]

Hi All,

I have been wondering lately if there have been calculations done on
the speeds that meteors stop their hot flight and enter dark flight.

What speed does a body have to reach before it generates a hot plasma
ball that shows as a fireball...or in other words how fast could a
body travel without becoming incandescent.

I know this is going to vary depending on altitude or thickness of
atmosphere and possibly size.

Has anyone seen data that shows this?

Cheers,

Graham