A white dwarf that has been dubbed a real-life Death Star (a spacecraft in the renowned “Star Wars” franchise) was spotted gobbling up a rocky body in its lethal orbit, as seen for the first time by humans and reported by scientists on Wednesday.
White dwarfs are the dead remains of stars, much like Earth’s own sun. When stars run out of hydrogen fuel, they start to cool and expand into a massive red giant. Afterwards they shrivel into a white dwarf.
Reporting in the journal Nature, graduate student Andrew Vanderburg from the Harvard-Smithsonian Center for Astrophysics and his team made groundbreaking observations from NASA’s Kepler spacecraft of the WD 1145+017 in the process of consuming a disintegrating rocky body.
“The white dwarf was ripping it apart by its extreme gravity and turning it into dust,” Vanderburg said, adding that the star was seen to have an asymmetric flicker, its light decreasing sharply and then gradually fading away.
According to Vanderburg, as the star lost its fuel, it eventually gave up, at which point its core collapsed in on itself and released its outer layer in an awe-inspiring farewell nebula. The remnant turned into a dense white dwarf with significantly strong gravity, such as the white dwarf Sirius B having one that is 350,000 times that of the Earth.
Calling their observation “watching a solar system get destroyed” as no human had seen previously, Vanderburg explained it further: fragments of a disintegrating planet being vaporized by the starlight of the white dwarf and losing mass. The vapor was getting lost into orbit, and that was condensing into dust and blocking the starlight.
Based on scientific observations, the altered pull of gravity would set the orbits of any remaining planets or rocky bodies off, where collisions would hurl the bodies’ pieces into the white dwarf. And what would happen to any planet that would stay too close to the dead star? It will get drawn in and shredded apart.
Chemicals common to rocky planets, including silicon, iron, aluminum, and magnesium, are also spotted in the atmospheres of about one-third of known white dwarfs, on top other heavy elements pulled by the stars’ staggering gravity.
The recent observations are said to support the belief that even if Earth, for instance, survives the sun’s red giant event, it will probably be consumed once the star turns into a white dwarf.
President of United Kingdom’s Royal Astronomical Society Martin A. Barstow dubbed the discovery “a key result” and “a nice experiment,” with the picture of a dying star consuming a rocky planet a welcome but unexpected feat.
