The TESS Space Telescope Mission
TESS is a NASA mission led by MIT and NASA Goddard to find transiting exoplanets around bright, nearby stars. Before its 2018 launch, the team projected roughly 20,000 possible planets across its broad survey; separate forecasts expected hundreds of Earth-sized and “super-Earth” planets suitable for follow-up. These were predictions, not a guaranteed number of discoveries.
“Within 200 light-years” is only a simplification. TESS targets stars relatively near the Sun; typical distances in the early survey were estimated at roughly 30–300 light-years, and some discovered systems lie outside that range. The mission was also not limited to Earth-sized planets: it searches across a broad range of planet sizes and orbits.