Kepler-16b

Kepler - 16b (formerly Kepler -16 ( AB )-b ) is an extrasolar planet. He is a Saturn -mass planet orbiting each half consists of gas and stone. It orbits the binary star Kepler -16 with a period of 229 days. " [ It ] is undoubtedly the first confirmed example ( ... ) a planet of not one but two stars orbiting ," said Josh Carter of the Harvard - Smithsonian Center for Astrophysics and a member of the discovery team.

Discovery and observation

The planet was discovered using the Kepler Space Telescope, NASA. Scientists had succeeded with the transit method to discover the planet after they observed that one of the stars of the system darkened without the other happened him. In addition, the accurate record of all occultations and passages of the planets and the stars of the system allowed an unusually accurate calculation of the sizes and masses of the objects in the Kepler - 16 system. Laurance Doyle, head of the research team that discovered the planet, said of this accuracy: "I think this is the best -measured planet outside the solar system. " For example, the radius of the planet can be determined to within 0.3 %, more accurate than any other exoplanets [ of September 2011 ].

Kepler - 16b is also interesting because the radius of its orbit is smaller than the assumed limit for planet formation in binary systems. After Sara Seager, a planetary expert at the Massachusetts Institute of Technology, one was previously assumed that a planet could keep a steady circular path in a binary star system, if this is at least seven times as far from the stars as the stars are to each other apart.

From Earth seen, the planet will have until 2014 happened the first star again and by 2018 crossing the second, brighter star. Then the planet with the transit method to about 2042 will not be more to discover.

The planet orbits at the outer edge of the habitable zone, but is probably a gas giant with a surface temperature between -100 ° C and -70 ° C.

Name

In the notification letter from the team wrote: " The principle Ref. 22 next, we can use the third body as Kepler 16 (AB )-b, or simply b ' denote, if no ambiguity exists. " In the SIMBAD database, it is used as Kepler -16 (AB )-b listed in the Extrasolar Planets Encyclopaedia he is as Kepler -16 ( AB) b registered.

The Smithsonian Center has informally as " Tatooine " spoken of Kepler - 16b, orbits a reference to the fictional planet from the Star Wars series, which has two suns. " Again and again we see that in science is something strange and stranger than fiction ," said John Knoll, who has worked at some of the films on the special effects.

Potential habitability

The habitable zone of the Kepler -16 system is located at a distance of about 55 to 106 million kilometers from the binary star Kepler -16 (AB). With an orbital radius of about 104 million kilometers is Kepler - 16b just at the outer edge of the habitable zone. Although the chances of finding themselves living on the gas giants, are small, have simulations, conducted by researchers at the University of Texas, demonstrated that possibly at some point in the history of the system a planet of Earth size disturbances of other bodies from the center of the habitable zone could have been driven, so that Kepler - 16b could catch him as the moon. In addition, researchers have considered the possibility that a more distant, habitable planet in about 140 million kilometers away could circle the double star, the thermal energy that is needed to keep water liquid through a dense mix of greenhouse gases such as carbon dioxide and methane, is achieved.