For the first time astronomers found eight planets outside the Solar system

© NASA / Ames Research Center/Wendy StenzelПланетная system Kepler-90For the first time astronomers found eight planets outside the Solar system© NASA / Ames Research Center/Wendy Stenzel

. Re-analysis of the pictures from the telescope «Kepler» has helped planetary scientists to open the eighth planet in the star system Kepler-90 in the constellation of the Dragon, that allowed her to break the record for the number of planets, which now holds the Solar system, according to a paper accepted for publication in Astronomical Journal.

«For the first time since the ancient times, when the first astronomers on Earth discovered neighboring planets, we know that the Solar system is not a record for the number of planets. We can say that Kepler-90 is a miniature analog of the Solar system – its internals inhabit a small planet, and outskirts of larger celestial bodies, but they are much closer to each other than Earth and its «cousin,» said Andrew Vanderburgh (Andrew Vanderburg) from the University of Texas at Austin (USA).

Over the past two decades, orbital and ground based telescopes have discovered thousands of planets outside the Solar system, some of which similar to Earth in size and properties, and the other on Jupiter and other giant planets. Most of these planets revolve around their stars or in solitude or in the company of one or two neighbors, similar in size and properties.

For this reason, planetary scientists believed that analogs of the Solar system are very rare – so far we know only three star system with seven planets, TRAPPIST-1 in the constellation of Aquarius, HD 10180 in the constellation Hydra and HR 8832 in the constellation Cassiopeia, as well as several dozen bodies, which surrounds a five or six planets.

Vanderburgh and his colleagues discovered the first star, which was compared in this respect with the Sun, re-analyzing the data that the telescope «Kepler» was collected in the first stage of its orbit when it is continuously watched the constellations Cygnus and Lyra for almost four years.

«Kepler» and other similar telescopes reveal traces of planets orbiting distant stars, watching for sharp changes in the brightness of the lights in the moment when one or more planets pass through their drive and block part of their rays. This technique works well for large planets located close to stars, but her work is beginning to interfere with the fluctuations in brightness of the light and other random factors, if they are far away from the stars.

From the interference can be eliminated in two ways — increasing the duration of observation or cleaning the data from accidental changes in the brightness of the lights with the help of new statistical algorithms and artificial intelligence systems. Members of the research team «Kepler» frequently use such algorithms for re-analysis of already collected data, checking the existing of the planet and trying to open a new one.

Space Guinness book

Spending the next such a test, Vanderburgh and his colleagues noticed no unusual anomalies in the behavior of the planets orbiting Kepler-90 – yellow dwarf star in the constellation Draco, remote from us at 2.5 thousand years.

This planetary system as previously thought by scientists, contained seven planets – two analogue of the Earth, b and c, three «super-earths» d, e and f, and two gas giant the size of Jupiter, g and h. Despite such a large number of planets and their fairly large size, this star system is very compact – it is the most distant planet, h located at approximately the same distance from Kepler-90, and Earth.

It tells Vanderburgh, enough scientists have long suspected that the first three planets Kepler-90 may be hiding another small rocky body, but could not prove it due to the presence of unambiguous data in favour of this and a large amount of interference.

This task was able to solve the neural network, which NASA scientists have learned to distinguish between actual passages of the planets over the disk of lights and random changes in their brightness, «showing» her about 15 thousand correct examples. Using this system, the AI, Vanderburgh and his colleagues were able to discover another planet in Kepler-90 and calculate its properties.

This planet, received a temporary name i, is between planets C and d, and makes one revolution around the star in just 15 partial days. It is about three times closer to Kepler-90, than mercury to the Sun, so its surface reigns hell’s temperature is about 700 degrees Kelvin. In terms of chemical composition, size and mass it is similar to Earth, but life on its surface, such temperatures are unlikely to exist.

Its opening, according to the Vanderburgh, makes the mystery of the formation of this star system even more interesting for scientists – it is not clear how such a large and complicated planetary family was able to be compact and keep howling stability. Scientists do not exclude that in Kepler-90 may be hiding a larger number of planets that the neural network can not yet «see.»