Copy to Clipboard An artist's illustration of TOI-561 (WM Keck Observatory/Adam Makarenko) One of the oldest stars in the Milky Way galaxy hosts an unusually hot and rocky “Super-Earth” planet. Known as TOI-561b, the planet orbits the star TESS Object of Interest (TOI) 561, named for the ongoing NASA Transiting Exoplanet Survey Satellite or TESS planet-hunting mission. The planet is unlike any other Super-Earth found to date, according to scientists. It is about 50% larger than Earth but requires less than half a day to orbit its star. According to experts, for every day on Earth, this planet orbits its star twice.