Two particularly strange stars may have formed in a lucky collision, according to new research.
What makes these two things stars anomalies are the high levels of carbon and oxygen on the surface of their atmospheres. Those elements are left behind when a star burns off its helium, but that process takes place in the star’s core and ends long before carbon and oxygen begin to dominate the star’s atmosphere. Curiously, these stars still seem to run through helium despite their strange surfaces.
Klaus Werner, an astronomer at the University of Tübingen in Germany and lead author of a new study, said: “Typically, we would expect stars with this surface composition to have burned up all the helium within a short period of time. their cores and are on their way to becoming white dwarfs. of these strange stars, said in a statement from the Royal Astronomical Society (RAS), has published new research in its journal. “These new stars present a serious challenge to our understanding of stellar evolution.”
Specifically, the scientists looked at two stars named PG1654+322 and PG1528+025. Except for the high amounts of carbon and oxygen in their atmospheres, these two stars look like small stars and Another hot is on the way to become white dwarfdense “star bodies” are left behind when small and medium stars run out of fuel to burn.
And yet, because of the size and temperature of these two stars, astronomers believe these objects are still burning helium. But typically, stars exhibit the light elements hydrogen and helium at their surfaces, rather than the much heavier carbon and oxygen.
A second group of scientists has proposed a hypothesis for how these strange stars might have formed.
Marcelo Miller Bertolami, an astronomer at La Plata Institute for Astrophysics in Argentina and lead author of the second paper, said in a RAS statement.
“Usually, white dwarf mergers do not lead to the formation of carbon and oxygen-rich stars, but we believe that, for binary systems, are formed with very specific masses,” said Miller Bertolami. , a carbon and oxygen-rich white dwarf can break apart and end up on top of a helium-rich star, leading to the formation of these stars. “
Even with that explanation, however, the observations astronomers have collected aren’t completely complementary, and scientists aren’t sure how the collision would have happened in the first place. . That means researchers especially want to focus on models that explore the behavior of binary stars, before merging.
https://www.space.com/strange-stars-helium-ashes-white-dwarf Incredibly rare star mergers may have created strange stars