Astronomers found a sun-like star exoplanet’s size and mass similar to Earth. As reported in the journal Astronomy & Astrophysics, celestial body may be located in a potentially habitable zone, and the average surface temperature under certain conditions shall be equal to five degrees Celsius.
Over the past 14 years using telescopes such as Kepler, CoRoT, and TESS, astronomers were able to detect more than four thousand planets. Most of them gas giantssimilar to Neptune or Jupiter, which rotate in relatively close orbits around their stars. However, scientists are often encountered and rocky exoplanets similar to our Earth, and some of them are located in a potentially habitable zone, that is where a heavenly body is getting enough of the body to its surface could be liquid water.
However, the vast majority of Earth-like bodies known to astronomers today revolve around red dwarfs. Red dwarfs are very small and faint stars, which have a greater life expectancy and emit primarily in the infrared range. To get to the habitable zone of such stars, the planets should revolve around them at close distances. On the one hand, this advantage, as during the year this object makes multiple transits, the transits across the stellar disk, and it’s easier to register and to learn, but on the other hand, red dwarfs are also known to often experience a powerful flash, and proximity to them could sterilize the planet, even if formal conditions are suitable for life. So much more interesting from this point of view represent a celestial body from twins of the Sun.
Rene Heller (René Heller) from the Institute for the study of the Solar system max Planck Society together with colleagues examined archival data of the telescope “Kepler” about the star Kepler-160, remote from us in 3 thousand light years. She was in a field of view of the instrument from 2009 to 2013. The radius of Kepler-160 equal to 1.1 sun and effective temperature of its surface less than that of our sun, all at 300 degrees Celsius. In addition, for stars of similar luminosity, making them almost “twins”.
In the past, Kepler-160 was open two planets: Kepler-160c and Kepler-160b. They are both much more Ground and rotate in a close orbit around the sun. However, the group of Heller noticed that in the time of transits of Kepler-160c, there are significant deviations that could be explained by the presence of other celestial bodies in the system and the influence of their gravity. To test their hypothesis, the researchers developed a new algorithm to register even small changes in the light curve of the star (which is important when searching for small planets at great distances), and also conducted a simulation of changes in the brightness of stars in the presence of another planet.
Data showed that around Kepler-160 can rotate two planets, and one of them, called KOI-456.04, must have a mass of 1.9 earth. The orbital period of a celestial body is 378 days, which is close to the duration of the year on our planet and on its surface falls almost the same radiation. Furthermore, it is located in a potentially habitable zone and the star shines mostly in visible range of the electromagnetic spectrum.
According to scientists, the conditions on the surface of the KOI-456.04 may resemble earth, but only under the condition that the gas envelope of a celestial body is not too massive and not like us. If the atmosphere of the candidate planet is filled with inert gases and in it there is a moderate greenhouse effect, the average surface temperature of the Earth twin may be five degrees Celsius, ten degrees below the average temperature of our planet.
Currently, however, we cannot completely exclude the possibility that KOI-456.04 is a statistical Fluke or systematic measurement error. By estimates of authors of work open to them, the signal could belong to the planet with a probability of 85 percent, while in order to admit the candidate exoplanet in a real object, the probability shall be 99 percent. Perhaps in the future astronomers will be able to check the reliability of the opening, for example in the framework of the PLATO mission by the European space Agency.
Recently, astronomers reported the discovery of another Earth-like planet, missed the “Kepler”. Known today it is most similar to ours in size and design temperature.