Studying exoplanets has given astronomers insights into the characteristics that could help them find life beyond Earth. For years, astronomers thought an exoplanet’s location in a star’s habitable zone was enough to make it an Earth-like world. But some stars are more active than our sun, exposing planets in their habitable zones to far more radiation than Earth receives. Astronomers have increasingly recognized that a planet’s magnetic field, which shields Earth from harmful radiation, could be a key characteristic in identifying Earth-like worlds.
