On Thu, 28 Aug 2003 17:05:10 +0000, Robert Ehrlich
wrote:

. My idea was that the speed of sound, while
affected by the change in conditions, should not be affected by a very important
factor. The factors involved are absolute temperature, molecular weight of the
gas(es) and gamma (Cp/Cv). Gamma depends only on the atomicity. While I don't
know exactly what are the components of the martian atmosphere, I guess it is
not methane or CO2, but rather diatomic gases with molecular weigth near O2 and
N2 as found on the earth. As all this is under a square root, changes must be
huge to become significative, same thing for temperature. Halving the temperature
on earth only decreases the speed of sound by a factor 0.7, and this is pretty
cold.

So 10 times the gliding speed on the earth is about the speed of sound on the earth,
if the reduction of gravity and wing loading gives a factor that overrides
the change in the speed of sound, subsonic soaring may be possible on Mars.


The Martian atmosphere is mostly CO2. Anyone have a number for the
speed of sound in CO2 at say 220 degrees K ? Then we can do the real
numbers.

Mike Borgelt