NASA’s Kepler space telescope will continue its search for exoplanets in the fourth campaign of its K2 mission. The fourth campaign will run from February 7 to April 24. Kepler will search nearly 16,000 target stars and two open star clusters – the Pleiades and Hyades – for exoplanets and other phenomena. In particular, it will search for sun-like stars with earth-like planets.
In its previous campaigns 0-3, the telescope has found more than 1,000 exoplanets, of which 8 are in their suns’ habitable zones. Data from Kepler’s Campaigns 0, 1 and 2 can be accessed by the public at the Mikulski Archive for Space Telescopes (MAST). Data from Campaign 3 will be available there from June 2015.
Since its launch in 2009, Kepler has been following the quest for other worlds like ours. Looking for earth-like planets orbitng other stars, scientists have found three types of exoplanets. There are the gas giants, the smaller, hot-super-Earths in short period orbits, and ice giants. The big prize in this search is for terrestrial planets – planets like earth, similar in size (or half to double the size) and orbiting in the habitable zones of their suns. The habitable zone is understood as a zone with temperatures where liquid water might exist on the planet’s surface.
Kepler detects planets by the Transit Method. A planet transiting across its sun’s surface reduced its brightness by a tiny amount. Kepler looks for periodic dips in the brightness of the stars it is monitoring. The orbit, size and temperature of the planet can be calculated using the orbital period, the mass of the star, the depth of the transit and brightness of the star, and the temperature of the star.
From our earliest history, humans have wondered if life existed outside our planet. Kepler is on the way to providing answers to that question. In March 2015, the Kepler team won the highest achievement award from the Smithsonian National Air and Space Museum. The Kepler telescope will continue functioning until 2017, when it is expected to run out of fuel.