A white dwarf of record density was discovered

The celestial body can explode at any time.

A white dwarf of record density, with a huge mass relative to its small size, has been discovered in the Milky Way, about 130 light-years from Earth.

Scientists report that the highly magnetic and fast-circulating white dwarf is 35 percent more massive than the Sun, but 4,300 kilometers in diameter, so only slightly larger than the Moon.

This means that it has a mass greater than all the white dwarfs known so far, yet has the smallest size, and its density is enormous.

While the period of rotation of the Sun about its own axis is about 27 days, that of the white dwarf is seven minutes. Its magnetic field is roughly a billion times stronger than that of the Earth.

White dwarfs represent the final stage of stellar evolution, are usually roughly Earth-sized and 100 times smaller than the Sun.

Their mass is approximately equal to the mass of the Sun, so their density is very high. White dwarfs have extremely high surface temperatures and therefore emit bright white light.

Only two other types of celestial bodies, black holes and neutron stars, have a higher density than white dwarfs.

The birth of ZTF J1901 + 1458, a white dwarf, was also unusual, as observed by Kevin Burdge of the Palomar Observatory at the University of California, Caltech near San Diego. It appears to be the product of a dual star system in which two stars revolved around each other. At the end of their life cycle, these two stars separately turned into white dwarfs, then spiraled towards each other and melted into a single unit.

With a slightly higher density, the result of the merger would have been a huge starburst, or supernova, said Ilaria Caiazzo, a Caltech astrophysicist and lead author of a study on the discovery in the scientific journal Nature.

According to Caiazzo, this white dwarf has really extreme qualities. “We found an object that is on the verge of how small and how mass a white dwarf can be,” he said.

He added:

the celestial body can explode at any time.

The white dwarf gradually shrinks, making it denser. If it does not explode, it can lead to the collapse of its core, making it a neutron star. This may be a previously unknown pathway for the formation of neutron stars, scientists believe.

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