Astronomers may have discovered Sun's identical twin

The researchers think they have finally found a star identical to our sun. The new object, dubbed HD186302, is a G3-like main sequence star similar to our sun in terms of age and chemical composition. Moreover, it is not only a solar brother, but also a solar twin.

Stars are not usually born alone. They form in massive star clusters and even in binary star systems, which means that almost all newborn stars have a companion. But to explain why some stars are solitary while others have two or three companions is a mystery.

Astronomers have also long sought a companion for our sun. They believe that thousands of stars have formed in the same massive cluster as the sun about 4.6 billion years ago. But the cluster eventually dispersed and the stars inside dispersed across the galaxy, making their search very difficult.

The idea that all stars are formed with a companion has important implications, not only for the activity of stars, but also for the formation of these stars in galaxies.

"Since there is not much information about the sun's past, studying these stars can help us understand where in the galaxy and under what conditions the sun has formed." Vardan Adibekyan .

In the last effort, researchers used a new method to detect solar siblings. They took a sample of 230,000 spectrums from the AMBRE project, a galactic archeology project set up by the European Space Observatory. Then, they combined these very high quality spectral data with recent astrometric data extracted from the European Space Agency's GAIA mission and selected stars of similar chemical composition, age, and kinematic properties as the sun.

By comparing the results of the AMBRE project with the GAIA data, the researchers discovered a single solar brother. Solar brothers and sisters are ideal candidates to seek life beyond our solar system.

Said Vardan Adibekyan. "Some theoretical calculations show that there is a significant probability that life will spread from Earth to other planets or explanatory systems, during the period of late intensive bombardment. If we are lucky and our brother candidate has a planet and the planet is rocky, in the habitable zone, and finally if this planet was "contaminated" by the seeds of the Earth, then we have what we could dream – a 2.0 Earth, orbiting a 2.0 sun. "