(Inside Science) -- The Transiting Exoplanet Survey Satellite (TESS) was built and successfully launched in 2018 to hunt for planets outside of our solar system. The $287 million instrument has located more than 2,000 potential exoplanets, with 91 of them already confirmed. TESS detects exoplanets by monitoring the brightness of stars. Stars dim temporarily when an object passes in front of them, like the silhouette of Santa’s sleigh on the moon. The approach is called the transit method.