Kepler-138b: Astronomers Measure Mass of Mars-Size Exoplanet

Astronomers using data from NASA’s Kepler mission have determined the sizes and masses of three planets orbiting a star much fainter and cooler than the Sun, known as Kepler-138, including the Mars-size exoplanet Kepler-138b. Determining the size of an Earth-size exoplanet by the amount of starlight it blocks hundreds of light-years away once was the [...] —> Read More