A hypervelocity star is a fast-moving star that moves more than twice as fast as most other stars — More than 1.7 million kph (500 km/s).
Astronomers first discovered these stars in 2005. Nearly 30 HVSs have been discovered so far.
Moving at a speed of 2.3 million mph (1,017 km/s), the newfound hypervelocity star is moving so fast that it will leave the Milky Way and head into intergalactic space.Named the S5-HVS1, this star is at a distance of about 29,000 light-years.
When integrated backwards in time, the orbit of the star points unambiguously to the Galactic center, implying that S5-HVS1 was kicked away from Sagittarius A* with a velocity of 4 million mph (1,800 km/s) and traveled for 4.8 million years to its current location.
Scientists have said that S5-HVD1 lived with a companion in a binary star system. The binary system got too close to Sagittarius A which engulfed the companion star and tossed S5-HVD1 away.