Dish in radio astronomy, another word for antenna. Doppler Effect an effect in which the frequency of light or sound coming moving object is different when it is received compared to when it was emitted. How much the frequency changes depends on how fast the object is moving toward or away from the receiver. The full range of frequencies, from radio waves to gamma waves, that characterizes light. Another term for light.
Light waves are fluctuations of electric and magnetic fields in space.
Evolved Star A star near the end of its lifetime when most of its fuel has been used up. This period of the star's life is characterised by loss of mass from its surface in the form of a stellar wind. A Fourier Transform is the mathematical operation that takes measurements made with a radio interferometer and transforms them into an image of the radio sky. The Fast Fourier Transform is technique used by computer programs that allows the Fourier Transform to be computed very quickly. Frequency a property of a wave that describes how many of wave patterns or cycles pass by in a period of time.