The velocities of air molecules at those altitudes where artificial satellites fly correspond to temperatures of several thousand Kelvin

The velocities of air molecules at those altitudes where artificial satellites fly correspond to temperatures of several thousand Kelvin. Why don’t the satellites melt as they move?

The concentration of molecules and atoms of air at high altitudes is so small that they cannot transfer to the satellite the amount of heat that is necessary to melt it. But this effect turns out to be significant at altitudes below 100 km.