Scientists continue to find so-called “double-faced” white dwarfs whose chemical composition of various hemispheres is very different. They have recently discovered two more such objects, which had previously remained completely unknown.
Double-faced white dwarfs
A team of astronomers and astrophysicists from several universities and research centers in the United States recently reported the discovery of several white dwarfs of a rare type. Its first representatives were only discovered a couple years ago.
White dwarfs are extremely compact and dense objects that form after a star has exhausted almost all of its thermonuclear fuel, passed the red giant stage, and shed all of its outer shells.
Usually the outer layers of a white dwarf are composed of hydrogen. There are also objects with shells of helium and oxygen. However, two years ago, scientists found a very unusual dead star. One hemisphere is helium, the other hydrogen. The luminary turns to us from one side to the other.
New discoveries
Previously, scientists were aware of two “double-faced” white dwarfs. A new study has found the same feature in five more dead stars. And scientists still did not know about the existence of two of them at all. However, it is now clear that such strange objects are rare, but not isolated.
Scientists also note that at least four of the seven currently known “double-faced” white dwarfs have extremely strong magnetic fields. No ordinary representative of this type of object has anything like this.
Therefore, scientists speculate that it may have something in common with the “double-facedness” of these stars. Perhaps the magnetic field is stronger at the poles, and it stretches different gases in opposite directions.
According to phys.org
