The First Exoplanets Are Confirmed

Setting the scene

Astronomers long assumed other stars hosted planets but lacked proof; pulsar timing offered a precision laboratory when Polish-born Penn State professor Aleksander Wolszczan detected periodic anomalies in radio pulses from PSR B1257+12.

What happened

Aleksander Wolszczan confirmed exoplanets in 1992, announcing two Earth-mass worlds and a later third orbiting the millisecond pulsar 2,300 light-years away in Virgo.

Why it still matters

Thousands of worlds were found in decades after via Kepler, TESS, and radial-velocity surveys; Wolszczan's pulsar planets remain bizarre—baked by radiation—yet opened the exoplanet era that now catalogs habitable-zone 'Earth cousins' nightly.

Background

Thousands of worlds were found in decades after.