NASA’s Kepler Team announced one of their most exciting discoveries to date on Thursday, Kepler 452b. Earth’s larger cousin is located in the habitable zone of a G2 main-sequence star like our own in the constellation Cygnus, 1400 light years away.
Kepler 452b was detected by the Kepler spacecraft’s nearly meter-wide Schmidt telescope, equipped with a sensitive 95 megapixel CCD array, by watching the light from the star KIC 8311864 (about 2 degrees from Delta Cygni) dim as the planet made its 10.5-hour pass in front of it, called a transit. The transit was observed 9 more times.
452b is 60% larger than earth and orbits its star in 385 days, a mere 20 days longer than our own orbit. It is estimated to be about 6 billion years old, more than long enough to have allowed for the development of life. Although the planet sits slightly farther away than Earth does to our Sun, Kepler 452b’s star is slightly larger providing roughly the same energy to the planet.
The Kepler spacecraft was launched in March 2009 on an extra-solar planet hunting missing that has yielded 1,030 confirmed exoplanets and identified 4,661 candidates for further observation. Kepler was designed to locate smaller, earth-like, planets that have been difficult to find until now. Kepler 452b is the smallest planet to date found orbiting in the habitable zone of a Sun-like star.