Physics
posted by Archillis on .
A radio station broadcasting on a frequency of 106 MHz is received by an astronaut headed toward the station at a speed 4.0×107 m/s. To what frequency must the astronaut's radio be tuned?( use MHz for final unit answers)

Use the relavistic doppler shift formula.
It does not depend upon which object is moving; only the relative velocity matters. The formula can be found at
http://en.wikipedia.org/wiki/Relativistic_Doppler_effect
and probably also in your textbook.
In your case, the relative velocity is 0.133 of the speed of light.
The received frequency will be higher by a factor
sqrt(1.133/0.867) = 1.143