April 1, 2021 When the TESS planet hunter launched nearly 3 years ago, some 4,000 exoplanets were known. NASA confirmed in late March that TESS has discovered over 2,200 additional exoplanet candidates orbiting distant stars. NASA’s TESS space telescope has found more than 2,200 exoplanet candidates so far, including hundred of smaller rocky worlds. Image via NASA. A few decades ago, astronomers thought planets orbited other stars, but they hadn’t really seen any. Now, we know thousands of distant planets – known as exoplanets – of the billions thought to exist in our Milky Way galaxy. Most exoplanet discoveries have come from space-based telescopes like Kepler. That mission ended with more than 4,000 exoplanets known, but the Transiting Exoplanet Survey Satellite (TESS) has taken over where Kepler left off, and, as of last month (March 23, 2021), NASA said that TESS has found over 2,200 additional candidate planets – called TESS Objects of Interest (TOI) – orbiting bright nearby stars. Hundreds of those may be smaller, rocky worlds like our Earth.