Samuel Albert Schaaf has written:

'Flow of rarefied gases' -- subject(s): Gas flow

J. E. LaGraff has written:

'Unsteady transonic heat transfer in a transient facility' -- subject(s): Solid surfaces, Rarefied gas dynamics, Gas flow, Aerodynamic heat transfer, Transonic flow, Unsteady flow

The gas molecules are very rarefied.

The stratosphere is a rarefied gas; solids are possible only as minute impurities.

Oxygen accounts for 42% (by volume) of an extremely rarefied atmosphere.