A lately found star in a remote dwarf galaxy is chemically alike to stars found in our galaxy's "halo," supporting the thought that the Milky Way "ate" other galaxies.
Astronomers said the star, found in the Sculptor galaxy 280,000 light-years away, is extremely low in "metals,”. In astronomy, metals are any elements other than hydrogen and helium.
Such metal-poor stars are considered to be very old, since they were uncommon in the premature universe. Elements heavier than helium are shaped as a result of star evolution processes, such as nuclear fusion, fission and supernovas.
"This star is probably almost as old as the universe itself," said astronomer Anna Frebel of the Harvard-Smithsonian Center for Astrophysics, lead author of the paper relating the star in Nature this week.
Frebel and her contemporaries used high-resolution spectroscopy to search the star for 11 diverse chemical elements, and found that its composition is similar to stars found in the Milky Way's "halo."
The halo stars contain metal levels 100,000 times lower than those found in the sun. The star originates in the dwarf galaxy, called S1020549, and has metal levels 4,000 times lesser than the sun, much lower than any other star in a dwarf galaxy.
The spectroscopic results came as of the Magellan-Clay telescope in Las Campanas, Chile.
The finding ropes the theory that the halo produced by the Milky Way gobbling up stars from smaller galaxies, the researchers said.
"The original plan that the halo of the Milky Way was created by destroying a lot of dwarf galaxies does indeed appear to be correct," said Josh Simon, an astronomer at the Observatories of the Carnegie Institution, in a declaration.
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