An international team of scientists analyzing data from NASA’s Kepler mission, has announced the discovery of the first small, potentially rocky planets. Named Kepler-62e and Kepler-62f, orbiting in the Habitable Zone of Kepler-62 star, that is slightly smaller and cooler than our own Sun. Image © David A. Aguilar (CfA)
Above: The newly discovered planets named Kepler-62e and -f are super-Earths in the habitable zone of a distant sun-like star. The largest planet in the image, Kepler-62f, is farthest from its star and covered by ice. Kepler-62e, in the foreground, is nearer to its star and covered by dense clouds. Closer in orbits a Neptune-size ice giant with another small planet transiting its star. Both habitable-zone planets may be capable of supporting life.
Going by their radii, these planets should be rocky, making them our best candidates for habitable planets out there yet. Analysis by Dr. Kaltenegger indicates that both planets lie in their host star’s habitable zone – where liquid water is possible, the necessary precondition for life as we know it.
The habitable zone (in which liquid water on a planet’s surface can exist) for different types of stars. The inner planets of our Solar System are shown on top, with Earth and Mars in the habitable zone. Kepler-62 is a notably cooler star, and Kepler-62e and -62f are in its habitable zone. For Kepler-69c, another planet announced today by NASA, the error bars for the star’s radiation are such that it could possibly in the habitable zone as well. Kepler-22b, the smallest planet found in a habitable zone before the recent discoveries, is very likely a Mini-Neptune, and not a solid planet. In what is denoted the empirical habitable zone, liquid water can exist on the surface of a planet if that planet has sufficient cloud cover. In the narrow habitable zone, liquid water can exist on the surface even without the presence of a cloud cover.
Kepler-62 system. Five planets, two of which are in the Habitable Zone.
The newly discovered exoplanets Kepler-62e and Kepler-62f
Lisa Kaltenegger (Max Planck Institute for Astronomy & Harvard-Smithsonian Center for Astrophysics) on the newly discovered, potentially habitable planets Kepler-62e and Kepler-62f – the best candidates for habitable, earth-like planets we know.
Kepler-62 is a star somewhat colder and smaller than the Sun in the constellation Lyra, located 1,200 light years from Earth. It is located within the field of vision of the Kepler spacecraft, the satellite that NASA’s Kepler Mission uses to detect planets that may be transiting their stars. On April 18, 2013 it was announced that the star has 5 planets, two of which, Kepler-62e and -62f are likely solid planets within the star’s habitable zone.