Dead star caught syphoning off debris from shattered objects in planetary system

Using archival data from the NASA/ESA Hubble Space Telescope, astronomers have, for the first time, observed a white dwarf star syphoning off debris from shattered objects in a planetary system.

For the unversed, a white dwarf is what Sun-like stars become after they have exhausted their nuclear fuel. According to NASA, white dwarfs are common objects in the cosmos - roughly 98% of all the stars in the universe will ultimately end up as white dwarfs, including our Sun.

The latest findings are based on analysing material captured by the atmosphere of the nearby white dwarf star G238-44 and can help describe the violent nature of evolved planetary systems and the composition of its disintegrating bodies.

In this study, the estimated total mass eventually gobbled up by the dead star may be no more than the mass of an asteroid or small moon. While the presence of at least two objects that the white dwarf is consuming is not directly measured, it's likely one is metal-rich like an asteroid and another is an icy body similar to what's found at the fringe of our solar system in the Kuiper belt, NASA said in a statement on Wednesday.

Astronomers measured the presence of nitrogen, oxygen, magnesium, silicon, iron and other elements. The detection of unexpectedly high nitrogen abundances led the team to conclude the presence of icy bodies.

"The abundances of the elements we see on this white dwarf appear to require both a rocky and a volatile-rich parent body – the first example we've found among studies of hundreds of white dwarfs," said Benjamin Zuckerman, UCLA professor and co-author.

For the first time, @NASAHubble astronomers saw a white dwarf star siphoning off debris from the inner and outer reaches of its system—giving us insight into the interior makeup of other planets. https://t.co/xmhqJH8Tdz pic.twitter.com/ZXUSnnt7L5

— NASA (@NASA) June 15, 2022