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Astronomy

Exoplanet Detection via Transit Photometry and Radial Velocity

Quick fact

Most of the first exoplanets found were discovered by the radial velocity method, but the transit method has now found thousands—thanks to missions like Kepler—revealing that planets are common around other stars.

Why this is interesting

When you look at the night sky, the stars seem fixed—but some are actually moving, and a few even blink. How can we tell if that subtle dance is caused by an invisible planet?