NASA probe spots first Earth-sized planet

  1. NASA’s unmanned Transiting Exoplanet Survey Satellite (TESS) space telescope has discovered its Earth-sized exoplanet, called HD 21749c. Exoplanet is a planet which orbits a star outside the solar system.
  2. The exoplanet orbits its parent star HD 21749, which is 52 light years away from Earth. It is located in the constellation of Reticulum. Earth-sized HD 21749c circles its parent star once every 7.8 days.
  3. TESS has also discovered a warm sub-Neptune-sized world, called HD 21749b, in the same system. HD 21749b has about 23 times Earth’s mass and a radius of about 2.7 times Earth’s. It takes about 36 days to orbit around the parent star.
  4. NASA’s Transiting Exoplanet Survey Satellite is an all-sky survey mission that seeks to discover exoplanets around nearby bright stars. It was launched in April 2018, aboard a SpaceX Falcon 9 rocket.