After encountering the supermassive black hole in the center of the galaxy, astronomers sighted a star from the Milky Way at a speed of more than 6 km / h or 1,700 km / s.  The star moves so fast that it leaves the Milky Way in about 100 meters and sails the rest of its life through intergalactic space alone. Although it was predicted 30 years ago that black holes could eject stars from the galaxy at phenomenal speeds, such an event was recorded for the first time.
Gary Da Costa, astronomer and emeritus professor at the Australian National University (ANU) in Canberra said, "We traced the star's journey back to the center of our galaxy, which is quite exciting."
Da Costa and colleagues have determined that the star was part of a double star star system 5 million years ago, which had penetrated extremely close to Sagittarius A *, the location of the central black hole of the Milky Way, whose mass is more than 4 m suns two made a binary partnership with the star Black hole, which would eventually cause it to be swallowed up and forgotten. The dynamics of this interaction meant that the original partner was ejected at extremely high speed.
According to the astronomer Jack Hills, who proposed the scenario over 30 years ago, the process is referred to as the Hills mechanism.
"This star travels at record speed, ten times faster than most stars in the Milky Way, including our Sun," Da Costa said. "Astronomically, the star will leave our galaxy pretty soon, and probably wander forever through the emptiness of the intergalactic space." The other two were those that had been brought to high speeds in supernova explosions.
"Apart from these somewhat peculiar cases, this star is by far the fastest that has ever been discovered," said Dougal Mackey, co-author at the ANU College of Science.
The team made the discovery of the star with the 3.9-meter Anglo-Australian telescope at the ANU Siding Spring Observatory. The team studied stellar flows in the Milky Way galaxy that roll toward the galactic disk but have some spare capacity to look at other stars, and made the random discovery of S5-HVS1
After leaving the Milky Way Star, it will continue its journey through the intergalactic space. "It will continue and eventually end up as a white dwarf like our sun. It simply has no neighbors, "Da Costa said.
The results of the study are published in the Monthly Bulletin of the Royal Astronomical Society.