The white dwarf star LAMOST J0240+1952, located approximately 2,000 light-years from Earth, is the fastest-spinning white dwarf ever recorded.
Scientists at the University of Warwick (UK) discovered that the white dwarf star named LAMOST J0240+1952 spins at an extremely rapid pace, completing one rotation in just 25 seconds, as reported by Interesting Engineering on October 15. This means that a day on this star lasts only 25 seconds.
Illustration of a white dwarf star (left) spinning rapidly due to gas ejected from a red dwarf (right). (Image: NASA/Casey Reed)
LAMOST J0240+1952 is located in the constellation Aries, about 2,000 light-years from Earth, and is the fastest-spinning white dwarf ever discovered. Earth rotates on its axis once every day, while the Sun takes about a month to complete one rotation.
Ingrid Pelisoli, an astronomer at the University of Warwick, along with colleagues, discovered LAMOST J0240+1952 after noticing a burst of light from the white dwarf near a red dwarf star. They realized that this brief outburst occurred every 24.93 seconds, allowing them to determine the rotation period of the white dwarf.
Typically, white dwarfs take hours or days to complete one rotation. However, this newly discovered star spins so rapidly because it is being supplied with gas from a nearby red dwarf. Pelisoli’s research team presented their findings in the arXiv database.
White dwarfs are among the oldest observable celestial objects in the universe. They have also been the focus of several significant scientific observations in recent years. For example, last year, neutron stars and white dwarfs helped astronomers demonstrate Einstein’s theory of relativity by observing the phenomenon of frame-dragging, where space-time is altered by massive rotating objects.
Previously, astronomers at the University of Warwick revealed direct observations showing that thousands of white dwarfs in the Milky Way gradually crystallize as they cool over millennia. In the future, the Sun will undergo a similar process before cooling into a crystalline core. This discovery suggests that some white dwarfs are billions of years older than previously estimated. The oldest of these stars may even be as old as the universe itself. This means that exploring the mysteries of white dwarfs promises to provide valuable information about the history of the universe.
