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Old March 14th 11, 09:08 PM posted to rec.radio.amateur.antenna
Jim Lux Jim Lux is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default Radio waves faster than light

Speed of light in space is known thanks Roemer.s method. Now are radio
transmitters on the Mars and is possibility to use the Roemer's method for
radio waves. NASA know the results. Are thy pulished?


Of course, they're published. Widely. I would check Journal of
Geophysical Research or similar publications.

As a practical matter, precise measurements of the time of flight
to/from a spacecraft is used to figure out where the spacecraft is and
its radial velocity.

Typical range accuracy is on the order of a few meters, velocities good
to a few cm/s, for something at the orbit of Neptune or Uranus.

Precise doppler measurements are used for radio science experiments,
e.g. to determine the internal structure of a planet or moon by
precisely measuring the orbit of a satellite. A typical performance for
such a measurement is 1 part in 1E15 over 1000 seconds at 32 GHz or 8GHz.