Scientists believe that a star flying to the Sun will pass very close
In 1.35 million years, a star will fly near the Sun, sending many comets to the Earth and other planets. These conclusions were reached by Polish scientists, using updated data on the trajectory of this star.
A star half the size of the Sun is sweeping towards the Solar System at a speed of 51 thousand km / h. When it approaches the Sun, a cometary rain will fall on the planets, which will last for millions of years. However, it is too early to build shelters - it is expected to appear in about 1.35 million years.
As scientists from the Polish Adam Mickiewicz University in Poznan write in the journal Astronomy & Astrophysics, the star Gliese 710 is now 64 light years from the solar system. One light year is 9,461,000,000,000 km.
According to their forecasts, the star will pass the Earth in only 77 light days (for comparison, the closest star to the Earth apart from the Sun, Proxima Centauri, is at a distance of 4.22 light years).
According to earlier estimates, it should have traveled nearly one light-year, that is, five times further.
Gliese 710 will not collide with the Earth, but will pass through the Oort cloud - a region around the solar system consisting of trillions of comet nuclei larger than 1.3 km and which is the source of long-period (with a period of more than 200 years around the Sun) comets. Its outer boundaries are located at a distance of one light-year from the Sun. It is assumed that the gravitational field of Gliese 710 may cause disturbances in the cloud.
This will lead to the fact that objects in it in large numbers will fall into the solar system and with a high probability will crash into the Earth.
Promotional video:
"The star Gliese 710 will provoke a cometary rain of about 10 comets every year for 3-4 million years," the study authors note.
Polish astronomers used data obtained with the Gaia space telescope, owned by the European Space Agency. It was launched into orbit in 2013 to help scientists compile a detailed map of the distribution of stars in our galaxy, the Milky Way. It is assumed that with its help a three-dimensional map will be compiled showing the coordinates, direction of movement and spectral type of about a billion stars and about 10 thousand exoplanets will be discovered. According to experts, the new data is 10 times more accurate than the previous ones.
Gliese 710 had been considered the most likely candidate for a rendezvous with the solar system for decades, but until the data collected by Gaia, astronomers could not determine exactly how far it would travel.
Some scientists suggest that it was the passage of the star through the Oort belt 65 million years ago that caused the asteroid to fall to Earth, which caused the death of the dinosaurs.
However, the emergence of the Gliese 710 could cause more significant damage.
As the Gliese 710 comes close to Earth, it will become the brightest and fastest-moving observable object in the sky. As the authors of the study note, this will be "the strongest destructive collision in the future and in the entire history of the solar system."
According to Gaia, the Gliese 710 flyby will be the closest flyby of a star past the solar system in the next few billion years.
Flor van Leeuwen, an astronomer from Cambridge, called the work "a high-profile study refining the results obtained during the HIPPARCOS (High Precision Parallax Collecting Satellite) space telescope mission." HIPPARCOS was launched back in 1989 with the aim of measuring coordinates, distances and proper motions of luminaries. For 37 months of work, he collected data on more than a million stars.
Leuven notes that the combination of data from HIPPARCOS and Gaia allows astronomers to accurately determine the motions of many nearby stars.
As Gazeta. Ru previously wrote, the Russian astronomer Vadim Bobylev came to the conclusion that Gliese 710 was approaching in 2010. He used data from the HIPPARCOS telescope and found nine stars that will approach the Sun in the next couple of million years. The Gliese 710 comes up especially close. According to Bobylev's calculations, it should have passed two light years from the Sun and had an impact on the objects of the Kuiper belt - the belt of small bodies of the solar system located outside the orbit of Neptune. The gravitational effect of Gliese 710 could cause changes in the orbits of objects and increase the number of comets that will travel towards the Sun and giant planets.
Falling on them in large numbers, comets would spawn a swarm of meteor showers and create new meteoroid bodies.
In addition, according to NASA astronomer Paul Weissman, the star is capable of changing the orbit of Neptune. Weissman had previously studied the possibility of the Gliese 710 and the Sun getting closer together and concluded that it could be quite close. “It's nice to see that this assumption has been confirmed using better models and better data,” he said of Bobylev's study.
Gliese 710 isn't the only star to be wary of, said Leuven. There are also many red dwarfs, the exact paths of which are still unknown. Over time, Gaia will examine them and make measurements as accurate as the Gliese 710, or even better.
"It is likely that among these stellar dwarfs there are those that threaten the solar system with a collision," says Leeuwen. “We just haven't found them and measured them yet.”
Alla Salkova
