An Earth-like planet
The nearest habitable planet the size of Earth may be only 13 light-years away, according to a study published in the Astrophysical Journal.
Analysis of data from small red dwarf stars, which make up most of the stars in our galaxy, showed that 6% of them have similar planets.
One of the authors of the study, David Charbonneau of Harvard University, said that the results of the study will help in the search for extraterrestrial life.
“We now know the probability of finding habitable planets around the most common stars in our galaxy. Finding life outside the Solar System will be much easier than we thought, ” Charbonneau said.
Recently, the hunt for exoplanets has reached an all-time high. In the search for habitable planets, the Kepler telescope, NASA’s astronomical satellite designed to search for celestial bodies similar to Earth, has been the most successful. He studies a section of the sky, covering more than 150 thousand stars, and notes the characteristic dimming of brightness that occurs when planets moving in their orbits cover the stars, falling into the field of view of the telescope.
There are more than 800 exoplanets in the NASA catalog, most of which were discovered by the transit method. This method is based on observations of the passage of a planet against the background of a star. It allows you to determine the size, and in combination with the Doppler method, and the density of the planets.
However, the discovered exoplanets are just the tip of a huge iceberg. Based on the results of the study using other methods, it was found that an average of 1.6 planets revolve around each star.
But the main goal has always been to find a planet similar to Earth. The search method used to detect exoplanets allows you to find only the largest planets, and most of the planets in the catalog are much larger than Earth.
However, there are many planets whose size is comparable to the size of our planet. A recent study found that one in six stars has a planet of this size, located in an orbit close enough to the star. This means that there are approximately 17 billion such planets in our galaxy alone.
But orbits too close to the stars mean high temperatures on such planets, so scientists are interested in planets that are located at a distance from the stars that allows them to assume the presence of water in liquid form. It is necessary that the planets are located and not too far from the stars-so that they do not freeze. Finding planets at a strictly defined distance from the star, making them suitable for life, is called the habitable zone (Goldilocks zone).
The researchers who reported the discovery focused on planets close in size to Earth, in the habitable zones of red dwarf stars that are significantly smaller and colder than the Sun. This means that their habitable zone may be closer than that of the Earth in relation to the Sun.
Astronomers from the Harvard-Smithsonian Astrophysical Center used data from the Kepler telescope to find red dwarfs that would have similar planets.
Red dwarfs in our galaxy are two-thirds of all stars. Older galaxies have even more of them.
Researchers have discovered 95 planets around red dwarfs. Of these, 60% are smaller than Neptune.
However, analysis of the data revealed that the three planets have temperatures suitable for life and sizes comparable to those of Earth.