Most exoplanets are discovered as they transit, or move across, their parent stars. But a new study details the opposite scenario: As a giant planet crossed its host star, peculiarities in its transit signature revealed a new discovery about the star itself — in particular, a spot that occupies an enormous 7% of the star's surface and has lasted at least seven years.
Nearly 6,000 exoplanets — planets beyond our solar system — have been confirmed to date. While many methods have helped amass this trove, the most successful has been the transit method. This technique, which has helped to reveal nearly 75% of known exoplanets, measures the transient, tiny decrease in a star's brightness when an orbiting planet passes along the line of sight between the star and an observing telescope.
