NASA’s Kepler Mission Discovered its First Rocky Planet

NASA’s Kepler mission, using Kepler Space Telescope, in the first week of January 2011 discovered its first rocky planet named Kepler-10b. The discovery of this exoplanet is based on more than eight months data collected by the spacecraft from May 2009 to early January 2010.
  
Kepler-10b is more than 20 times closer to its star than Mercury is to our Sun and it (Kepler-10b) is not in the habitable zone. It measures 1.4 times the size of Earth and it is the smallest planet discovered ever outside our solar system. The planet is unequivocally rocky. It has a mass 4.6 times that of Earth and with an average density of 8.8 grams per cubic centre. The daytime temperature at Kepler-10 b is 2500 degree Fahrenheit hotter than lava flows on Earth. Intense radiation from the star has kept the planet from holding onto an atmosphere. Kepler-10b is located about 560 light years from Earth, revolving around a star which is twice as old as our sun.

Kepler’s ultra-precise photometre measures the little decrease in a star’s brightness that happens when a planet crosses in front of it. The size of the planet can be calculated from the periodic decrease in the brightness of star. The distance between the planet and the star is estimated by calculating the time between successive decrease as the planet orbits the star.

Kepler is the first NASA mission capable of finding Earth-size planets.Kepler-10 was the first star identified that had the potential to harbor a small transiting planet.