Based on the data obtained by the Kepler telescope, astronomers have discovered a new type of planetary systems with two stars. This work confirms that the planets revolving around the "two suns" are not rare exceptions, but are common in our galaxy. This work is published today in the journal Nature and was presented at the meeting of the American Astronomical Society in Austin.
The team managed to find two new planets orbiting the binary star system. A similar phenomenon was first discovered in September last year.
Discovered planets were named Kepler-34b and Kepler-35b.
Both of them revolve around the "binary star", which is a gravitationally bound stars that orbit each other. Although the existence of such celestial bodies, called "multiple planets to orbit" has long been predicted, they remained just a theory until the team discovered Kepler-16b in September 2011. They called Kepler-16b "Tatooine" because of its similarity to the planet’s orbit with a multiple of the epic "Star Wars."
"We have long known that these planets may exist in reality, but their discovery has been hampered by some technical reasons" - said astronomy professor Eric Ford. "The opening of Kepler-16b, 34b and 35b, showed that in our galaxy, the number of planetary systems with two stars in the millions."
These planets were discovered by measuring the intensity of light, which decreases when the planet passed between one of the two stars and the Earth. Furthermore, Kepler showed decrease in the intensity of light at the moment when one of the other stars is closed. The mutual gravitational attraction of stars and planets leads to a deviation from the regular schedule of their movement, allowing scientists to confirm the presence of planets and measure their mass.
Both planets are gas giants with low density. They are comparable in size to Jupiter, but much inferior to him in bulk. Compared with Jupiter Kepler 34 24 percent smaller and 74 percent less in weight. The complete cycle of rotation takes him 288 Earth days. Kepler-35 to 26 percent smaller and 88 percent less by weight, with the spins much faster - the whole cycle lasts 131 days.
Astronomers believe that planets are composed primarily of hydrogen and too hot to be habitable.
Climate multiple planets orbit can be much more complicated, because the distance between the planet and each star can vary throughout the orbital period, "- said Ford." As Kepler-35b, the amount of incident light ranges from 50 percent within one year earth. And Kepler-34b, "summer" sun gets 2.3 times more than the "winter." For comparison, in our case the earth, the amount of sunlight varies during the year only 6%.
Originally, NASA planned to stop receiving information from Kepler in November 2012.
"Astronomers are literally begging NASA to extend the Kepler mission until 2016, after he made a revolution in many fields, not only in the field of planetary systems", - said Ford. "I hope that common sense will prevail and the mission will continue."