Scientists have spotted an extremely rare type of tiny, ancient star which happens to be one of the oldest in the Milky Way galaxy. According to a report by ScienceAlert on Sunday (June 16), the star named CWISE J124909+362116.0 exceeds the galactic escape velocity at around 600 kilometres per second. The hypervelocity star is moving at such a speed that soon it would be thrown out into intergalactic space.
The star, which is an L subdwarf, was spotted by scientists as they were combing through telescope data for signs of the mysterious Planet Nine.
CWISE J124909+362116.0 (J1249+36 for short) is one of just a handful of hypervelocity stars identified in the Milky Way galaxy, the report said.
The discovery of the star was announced at the 244th Meeting of the American Astronomical Society.
The explanations for the star’s velocity
ScienceAlert reported on Sunday that there were many explanations for J1249+36’s velocity, and scientists explored three of those.
The first explanation:
Scientists said that the first explanation for the star’s velocity would be the expulsion from a binary system that includes a white dwarf star. Ultra-dense white dwarfs shine hotly with residual heat rather than fusion, and can be a bit unstable if they have a binary companion, they added.
The second explanation:
The second possibility which scientists said was of a many-body interaction that becomes unstable and meets one of the objects across the Milky Way. There are environments within the Milky Way that make these interactions more likely, namely globular clusters – dense globs that can contain millions of stars.
The third explanation:
The third explanation that scientists gave is that J1249+36 is not from the Milky Way at all, but one of the many satellite dwarf galaxies orbiting it. A study conducted in 2017 that examined the provenance of hypervelocity stars found an extragalactic origin plausible.
Scientists pointed out that it’s feasible for J1249+36, too.
(With inputs from agencies)