White dwarf debris disk, animation. The disk has been formed by an asteroid torn apart by the strong gravity of the central white dwarf. The debris disk consists of dust particles and rocky debris orbiting the white dwarf, an Earth-sized burnt out stellar core named SDSS J1228+1040. The narrow glowing arc is caused by gas produced by collisions within the disc. This glow was detected in observations obtained over a period of twelve years with the European Southern Observatory (ESO)'s Very Large Telescope (VLT). Animation published in 2015.