A team of researchers from the UK's University of Warwick has used data collected by the European Southern Observatory's (ESO) Very Large Telescope (VLT) to study a distant white dwarf. The data, which was collected over a period of 12 years, provides a rare, detailed look at the star remnant interacting with a disk of material – thought to be the remains of an asteroid. The research has the potential to answer questions about the eventual fate of our own Solar System.
The observations focused on a white dwarf, what's left of a Sun-like star that expanded to become a red giant, before shedding its outer layers, becoming a small, extremely dense remnant. The white dwarf in question, known as SDSS J1228+1040, is particularly interesting as it's surrounded by a disk of glowing gaseous material.
The researchers looked at data collected primarily by the Ultraviolet and Visual Echelle Spectrograph and X-shooter instruments installed on the VLT. The readings detailed the light emitted from the remnant star and the material surrounding it for a period from 2003 up until the present. With such a long timeline of data, the team was able to look at the system from different angles, building a more complete understanding of its nature.
Specifically, the researchers were able to accurately map out the gaseous material surrounding the white dwarf, confirming that it is indeed a disk, though it is not yet perfectly formed, exhibiting a lopsided structure.
The data led to the conclusion that the disk was formed when an asteroid interacted with the white dwarf, with its extremely dense gravity tearing it apart. The rings then formed in a similar manner to those of Saturn, though on a much larger scale. The distance between the white dwarf and the ring system is large enough for Saturn's rings to sit comfortably inside the gap.
The wealth of data provided by study of such rare, disk-bearing white dwarfs – only seven of which have so far been located – is helping us answer key questions regarding the fate of our own Solar System. Specifically, it could provide insights into the conditions that exist at the end of the life of stars, helping us to unravel the processes that occur, and ultimately gain a more complete understanding of our own star's inevitable demise some seven billion years down the line.