In the case of “cosmic cannibalism”, scientists have observed the remains of a star chewing through a planetary system. Data from the National Aeronautics and Space Administration's Hubble Space Telescope and other observatories allowed scientists to observe a white dwarf siphoning material from a planetary system.
NASA's retired Far Ultraviolet Spectroscopic Explorer (FUSE), the Keck Observatory's High-Resolution Echelle Spectrometer (HIRES), and the Hubble Space Telescope's Cosmic Origins Spectrograph (COS) and Space Telescope Imaging Spectrograph (STIS) were used to make the analysis.
A white dwarf is what remains of a star like the Sun at the end of its lifecycle. The celestial object is much smaller than the star it spawned from but has a much stronger gravitational pull. The observed white dwarf, G238-44, was found to be consuming rocky-metallic and icy material, the material that makes up terrestrial planets.
"We have never seen both of these kinds of objects accreting onto a white dwarf at the same time," said Ted Johnson, the lead researcher. "By studying these white dwarfs, we hope to gain a better understanding of planetary systems that are still intact."
The observations will allow scientists to better understand what makes up planetary systems in space, and also how new planetary systems form.
"Life as we know it requires a rocky planet covered with a variety of elements like carbon, nitrogen, and oxygen," said Benjamin Zuckerman, co-author of the study. "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."
While scientists have catalogued several planets through observation, the interior make-up of only one planet is known with any certainty – the Earth. The cosmic cannibalism allows scientists to observe what planets are made up of as the white dwarf continues to consume the nearby space material.
