A close-up look at the birth of a star has revealed a surprise: Not one new stellar body, but two.
In 2017, scientists using a new array of radio telescopes in the Chilean desert were observing a massive young star named MM 1a in an active star-forming region of the galaxy more than 10,000 light-years away. As they analyzed the data, they realized that MM 1a was accompanied by a second, fainter object, which they dubbed MM 1b. This, they found, was the first star’s smaller sibling, formed from the spray of dust and gases it holds in its gravitational pull. In a solar system like Earth’s, this “disc” can coalesce into planets.
“In this case, the star and disc we have observed is so massive that, rather than witnessing a planet forming in the disc, we are seeing another star being born,” astronomy research fellow John Ilee of the University of Leeds in England, who led the study, said in a statement.