Astronomers have discovered an exoplanet with an orbital period of 27 000 years

Each planet in our Solar system has considerably different from the rest of the orbital period of rotation around the Sun. For example, if the Earth's one revolution around the star takes exactly 365.25 days, the same Mars it takes almost twice the time – 686,97 days. Jupiter and other gas giants of the system orbital period is even stronger, ranging from 11.86 164,8 year to year. But even with this in mind, astronomers were not quite prepared for the fact that there are such systems, as, for example, CVSO 30.

In this star system, located about 1200 light-years from Earth, astronomers have discovered two candidates in exoplanets. Upon detection of both objects, the mass of each of which is several times the mass of Jupiter, an international team of astronomers used the transit, as well as direct observation method. The researchers found that at the time, as the orbital period of one planet is less than 11 days, another planet makes a full revolution around its star just once every 27 000 (twenty seven thousand) years old!

Interesting, this discovery, of course, is not only because it managed to surprise scientists, but also because when the detection of planets within the same system was used several not similar to each other search methods.

To date, the majority of the more than 2000 exoplanets detected have been found through indirect methods of observation. It is first and foremost about the so-called transit method of observation to determine the presence of planets by observing changes in the brightness of stars, which occurs as a result of the passage of planet in front of its star, method of measuring angular velocity, which allows to detect a planet through the detection of the gravitational effects that it has on star.

So, one of the planets of this system — CVSO 30b – ground 5-6 times the mass of Jupiter was discovered by astronomers in 2012, with the help of the transit method of observation. Scientists have found that a planet located at a distance of 1.2 million kilometres of the star (for comparison, the same mercury is 58 million kilometers from the Sun). The researchers describe the planet as a "hot Jupiter".

The Method of direct observation, in turn, used by astronomers are much less likely. To date, it was discovered a few exoplanets. The reason for this is that reflected from the planet's atmosphere the light is usually bright enough and blends in the background light of its home star, making it difficult to observe. In addition, this method is very demanding on the use of very high quality and precision equipment. However, compared with indirect methods, it can be more effective when it comes to the observation of objects located in the more remote regions of their star systems.

Thanks to the joint effort of an international team of astronomers who used telescopes the Keck Observatory on the island of Hawaii, the Very large telescope of the European southern Observatory in Chile, as well as the power of the Spanish Observatory of Kalar Alto, was discovered planet CVSO 30c located at the distance of about 666 astronomical units from its star.

Details about this discovery is published in the online library Arxiv.org. In his article, scientists from such prestigious institutions as the inter-American Observatory Cerro-Tololo, Jena Observatory, the European space Agency and the Institute of astronomy of max Planck, spoke about the methods they used to open exoplanets, and explained the importance of this discovery.

follow the star CVSO 30 two different methods allowed us to find a new candidate exoplanets

"[Object 30b and 30c] are themselves very unusual. CVSO 30b represents the first discovered using the transit method, exoplanet, whose age is only about 2.5 million years. It was first described in 2012. Everyone else discovered to her the same way the planet was much older. For a few hundred million years. For us was a real surprise that it has a planetary neighbour, being at least 662 astronomical units from the star, which is approximately equal to 662 distances from the earth to the Sun, and thus has a mass, which is only 0.4 from the solar. According to the standard model, the planets formed from the disc surrounding the star. However, we have never seen near the stars with such a low weight there was a major drive for the formation of such object" — explains project Manager and a member of the University of Hamburg and Jena Observatory Tobias Schmidt.

In Other words, this means that astronomers did not expect to detect two extrasolar planets with a mass several times the mass of Jupiter moving around such a small star as CVSO 30. However, the discovery of two extrasolar planets with such a difference in distance between them and their star was for the scientists even more awesome.

Resorting to a high contrast photometric and spectroscopic observations using the Very large telescope, the Keck telescope and Observatory Kalar Alto, an international group of researchers were able to detect the planet CVSO 30c with the help of the so-called Lucky Imaging. The system automatically selects only those frames of the same area of sky that were obtained in those rare happy moments, when the distortion from the atmosphere were minimal.

Brown dwarf of spectral class T in the representation of the artist

As a result, scientists have found exoplanets with a very wide orbit and a mass is 4-5 times larger than Jupiter. Turned out to be that the planet is also very young. Its age is less than 10 million years. Moreover, the spectroscopic data indicated it to be very unusual blue color, while most other candidates in exoplanets, as a rule, was presented in the red range of the spectrum.

Scientists say that the CVSO 30c is the youngest planet in this class, which also managed to detect directly. Further research CVSO 30c showed that, most likely, it is the first discovered "transit facility L-T-class", whose age is less than 10 million years. Usually transit facilities L-T-class include brown dwarfs – objects too large to be reviewed as a planet, and at the same time too small to be seen as stars. Usually find them surrounded by a massive cloud of gas and dust either completely devoid of any environment.

The Researchers suggest that in tandem with the planet CVSO 30b (which is incredibly close to the star the same system) exoplanet CVSO 30c, most likely, originally formed elsewhere and then been significantly departed from its star. At least the other guesses existing models of planetary formation, unfortunately, does not. However, Professor Schmidt notes that this assumption is at least trying to explain the profoundly strange nature of these exoplanets.

The importance of the discovery also stems from the fact that this is the first case when the search for planets within the same system was used two methods of observing transit and direct. And in this case benefited from both methods.

"Transit method, and a method of measuring radial velocities have disadvantages. For example, do not allow to find planets near young stars, as the increased activity of young stars creating problems in the observations. CVSO 30b was the first and youngest planet detected by these methods. The method of direct observation, in turn, is best suited for the search for and study of young planets, as they still complete the process of its formation and thus provide sufficient light for observation. We are very fortunate that in addition to the outer planets, very far away from its star, we managed to find another planet very close to its star in the same system."

"the Real benefit of the simultaneous use of the transit method and the method of direct observation is that observation in this case, becoming more detailed. We hope to learn more about the nature of its formation and, in particular, to find out how such systems are formed in General", — concludes Schmidt.