NASA planet-hunting telescope makes 3rd discovery in 3 months
NASAâs Transiting Exoplanet Survey Satellite (TESS) has found the third confirmed exoplanet HD 21749b in its first three months of observations. "It could be a water planet or have some other type of substantial atmosphere," NASA said. The planet is about three times Earth's size and 23 times its mass and has a surface temperature of around 150Â°C, NASA added.