Smallest planet discovered orbiting another star

NASA scientists have discovered the smallest planet yet found going around a star similar to our Sun. It is only one third the size of Earth, slightly larger than our Moon. Located 210 light years away in the constellation Lyra, this system has two more planets. The moon-size planet called Kepler-37b, and its two companion planets were found by scientists with NASA's Kepler mission, which is designed to find Earth-sized planets in or near the "habitable zone," the region in a planetary system where liquid water might exist on the surface of an orbiting planet. However, while the star in Kepler-37 may be similar to our

sun, the system appears quite unlike the solar system in which we live. Astronomers think Kepler-37b does not have an atmosphere and cannot support life as we know it. The tiny planet almost certainly is rocky in composition. Kepler-37c, the closer neighboring planet, is slightly smaller than Venus, measuring almost three-quarters the size of Earth. Kepler-37d, the farther planet, is twice the size of Earth. The discovery of such a tiny planet highlights the great advances in technology. The first exoplanets found to orbit a normal star were giants. As technologies have advanced, smaller and smaller planets have been found, and Kepler has shown that even Earth-size exoplanets are common.