Internet users, participants "civic" astronomical project Planet Hunters together with astronomers professionals from Yale University for the first time in history has discovered a planet in the system of four stars, according to a paper accepted for publication in Astrophysical Journal and posted in the electronic library of Cornell University.

Voluntary "hunters planets", which now includes about 40 thousand of Internet users, analyzing the data about the changes Shine 160 thousand stars gathered space telescope "Kepler". Their task is to find transits, fluctuations in brightness, associated with the passage of the planet on the background of the stellar disk. The project Planet Hunters support scientists from Yale University, who had co-sponsored the study.

The system KIC 4862625 the efforts of volunteers discovered a new planet, consists of two pairs of stars revolving around each other at a distance of about 1 thousand astronomical units (average radius of the earth's orbit).

The first pair (dwarf spectral class F weighing 1.5 Solar masses, and the dwarf class M with a weight of 0.4 solar) is the eclipsing binary - that is, one star passes in front of the other, from the point of view of an observer on the Ground, which changed their apparent brightness.

One of the "hunters planets" Qian YEK (Kian Jek) from San Francisco in may 2011 found in curve brightness other pair eclipsing pair KIC 12644769 features that could indicate the presence in the system of the third body. By this time the strangeness of the light curve was noticed by a group of professional tools, which, eventually, led to the discovery of the first circumbinary Kepler planet-16b - planet in orbit around a binary star.

After this the "hunters" began to be systematically explore zatmenie double stars in the hope of finding such a planet. In March 2012 one of them, Robert Galliano (Robert Gagliano)in light curve KIC 4862625 dimming similar to "tracks" planet. After further analysis by Kiana-YEK, "hunters" came to the conclusion that indeed found a new planet.

To confirm this discovery, astronomers from the Keck Observatory (Hawaii) tried to detect the presence of a planet by using another method is by measuring the radial velocities. This method consists in measuring the Doppler method is extremely small oscillations of stars, which arise under the action of gravity on the planet.

Data obtained by this method, confirmed that the system really is the third component of planetary masses.

Planet PH1 became the first planet in quadruple star system. Its radius is 6.18 radius of the Earth, on the size it is slightly more than Neptune. One revolution around its pair of stars she makes 20 days.

To date, astronomers know about ten planets in binary star systems.