Astronomers discovered six objects orbiting the supermassive black hole Sagittarius A * in the center of the Milky Way, most likely a merged star cloud.
The newly discovered group of objects is so different from any object in the galaxy that is so strange that researchers put them into a new class called the G object . The results of the study were published today in the journal Nature.
Object G is most likely a cloud of a newly formed star following the collision of a binary star system.(Photo: Science Alert).
The objects G1 and G2 first caught the attention of astronomers nearly two decades ago due to their orbits and distinct nature. They appear to resemble a giant cloud of gas about 100 astronomical units in diameter, extending their distance near the black hole, with a spectrum of dust and gas emissions. But G1 and G2 were not moving like clouds of gas but like stars, according to astrophysicist and physicist Andrea Ghez at the University of California, Los Angeles (UCLA).
Ghez and colleagues studied the Milky Way center for more than 20 years. Based on data collected, the team headed by astronomer Anna Ciurlo at UCLA found four more objects G3, G4, G5 and G6 . They have a slightly different trajectory than the G1 and G2. The researchers found that the class G object has an orbit from 170 to 1,600 years. Although they do not know exactly what they are, the appearance of G2 at the point closest to the black hole on the fund could be a big clue.
"At the time of the closest black hole, G2 showed really strange signs. We have observed this object before but it was not as strange as when approaching the black hole, which was stretched and lost most of its gas. "From a harmless object far away from the black hole, G2 was stretched and distorted in its most recent approach, losing its outer layer and solidifying, " Ghez said.
Previously, researchers thought that G2 was a cloud of hydrogen gas torn and sucked in by Sagittarius A * but that was not the case. The team believes that the answer lies in the super large binary star. The double star system is stuck in each other's orbit. They crashed into each other to form a big star. This process produces a massive cloud of dust and gas surrounding the new star about 1 million years after the collision."There must be something that keeps G2 in good shape and helps it survive the collision with the black hole. That's evidence that there's a star inside G2," Ciurlo said.
The remaining 5 objects in the group may also be the result of the merger of binary stars. Most stars in the center of the galaxy are huge and binary. Gravity around Sagittarius A * is strong enough to disrupt their orbits, resulting in a collision.