White dwarf star is the size of the moon but more massive than the sun

star and moon

The smallest white dwarf star ever found is about the same size as Earth’s moon, but more massive than the sun. It appears to be shrinking, which could lead to a colossal explosion.

Ilaria Caiazzo at the California Institute of Technology and her colleagues discovered this star, called ZTF J190132.9+145808.7, using the Zwicky Transient Facility in California. They then performed additional observations with other telescopes to confirm its properties.

The researchers found that it rotates extraordinarily quickly, spinning once every 6.9 minutes. The magnetic field strength at its surface ranges between 600 and 900 megagauss – more than 1 billion times stronger than Earth’s magnetic field.

The star, which is about 130 light years from Earth, has a radius of about 2140 kilometres, only 400 kilometres bigger than the moon. But it also has a mass about 1.3 times that of the sun, close to the limit for how massive white dwarfs can become. While most white dwarfs form from single stars at the ends of their lives, this one’s extreme mass indicates that it may be the end result of a merger of two progenitor white dwarfs.

If [the two progenitor white dwarfs are] both massive, then the final outcome is an explosion, a supernova… but if they are two not particularly massive white dwarfs, then the system can survive and create another white dwarf, a very peculiar one,” said Caiazzo in a press conference. “This one is really at that limit – it just avoided explosion.”

Because of the extreme pressure at its core, the researchers say that a strange atomic process may take place there that turns protons into neutrons, allowing it to become even more compact.

“It’s not only the smallest white dwarf ever found, it’s also shrinking,” said Caiazzo. “If this continues, it might collapse.” That collapse could result in either an extraordinarily dense neutron star or an explosion in the next few hundred million years. So the smallest white dwarf may not have permanently avoided exploding after all.

 

 

Comments

Post a Comment

Popular posts from this blog

Image
  Mercury          Mercury is the closest to the sun and first, no moon, terrestrial planet and smallest  planet of solar system. it revolve the sun faster than all the other planets, which is why Romans named it after their swift-footed messenger god. The Sumerians also knew of Mercury since at least 5,000 years ago. It was often associated with Nabu, the god of writing . Mercury was also given separate names for its appearance as both a morning star and as an evening star. Greek astronomers knew, however, that the two names referred to the same body, and Heraclitus, around 500 B.C., correctly thought that both Mercury and Venus orbited the sun, not Earth. NASA's MESSENGER spacecraft orbited Mercury for more than four years. this spacecraft is launch by Delta 7925H And it 1,107.9 kilograms  Among its accomplishments, the mission determined Mercury’s surface composition, revealed its geological history, discovered details about its internal magnetic field, and verified its p
Read more
Image
The Black Knight Satellite: A Hodgepodge of Alien Conspiracy Theories The Black Knight satellite conspiracy theory claims that a spacecraft of extraterrestrial origin is in near- polar orbit of the Earth, and that NASA is covering up its existence and origin. This conspiracy theory combines several unrelated stories into one narrative. A photo taken during the STS-88 mission claimed by some to show the Black Knight satellite is catalogued by NASA as a photo of space debris, and space journalist James Oberg considers it as probable debris of a thermal blanket confirmed as lost during the mission.                    Take a good look at the photograph above. NASA captured this image of a mysterious black object orbiting the Earth in 1998, during the first Space Shuttle mission to the International Space Station (ISS). The space agency refers to the strange entity as item STS088-724-66 in its catalogue of space junk floating in low-Earth orbit (within 1,200 miles ). Jerry Ros
Read more
Image
Venus     It's a cloud-swaddled planet named for a love goddess, often called Earth’s twin. But pull up a bit closer, and Venus turns hellish. Our nearest planetary neighbor, the second planet from the Sun, has a surface hot enough to melt lead. The atmosphere is so thick that, from the surface, the Sun is just a smear light. In some ways it is more an opposite of Earth than a twin: Venus spins backward, has a day longer than its year, and lacks any semblance of seasons. It might once have been a habitable ocean world, like Earth, but that was at least a billion years ago. A runaway greenhouse effect turned all surface water into vapor, which then leaked slowly into space. The present-day surface of volcanic rock is blasted by high temperatures and pressures. Asked if the surface of Venus is likely to be life-bearing today, we can give a quick answer: a hard “no.” Further, Venus may hold lessons about what it takes for life to get its start ­– on Earth, in our solar
Read more