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Astronomy

Spectroscopic Techniques for Measuring Stellar Radial Velocities

Quick fact

The radial velocity method has discovered thousands of exoplanets, including the first exoplanet orbiting a sun-like star, 51 Pegasi b in 1995.

Why this is interesting

A star that looks perfectly still in the night sky may actually be drifting towards or away from us. How can we possibly detect such motion from light-years away?