Kepler Spots Smallest Exoplanet

The Kepler Mission is a NASA space observatory designed to discover Earth-like planets orbiting other stars. Yesterday it spotted the smallest exoplanet, called the Kepler-10b. The planet has a diameter of about 1.4 times that of Earth (unlike the HIP 12044b which is bigger than Jupiter) and orbits its host star closer than the distance at which Mercury orbits the Sun.

Kepler looks for fluctuating light that comes from the host star. If it fluctuates regularly and shows the correct curve, it’s imminent that a planet is orbiting that host star. Kepler 10-b has an orbit period of less than a day (a year on 10b is 0.84 Earth days!) making it easy to calculate spot this planet.

Too hot to handle

After spotting the Kepler 10-b, follow-up observations using the Keck telescope in Hawaii have confirmed the planet and an approximate idea about the planet’s mass has been found. The 10-b weighs 4.6 times that of Earth, a lot heavier than our planet.

The temperature is probably Kepler-10b’s most striking feature. At the speed at which it orbits, the Kepler 10-b only has to be a fraction of distance away from its host star than Mercury is to the Sun (less than five percent). At that distance, the 10-b is too hot for liquid water to exist, leave aside living beings.

This experiment confirms that the Kepler is operating well and will be continuously searching for more planets.

via ars technica

Published Date: Jan 12, 2011 01:52 pm | Updated Date: Jan 12, 2011 01:52 pm