The host star of the newly discovered planet fragment is a white dwarf, known as SDSS J122859.93+104032.9. A white dwarf packs the mass of nearly an entire sun into a sphere 1 per cent of the sun's size. Observations of the white dwarf's debris disk support this notion. Manser and his colleagues aren't sure what exactly is causing the gassy disturbances in 1228's debris disk. An alternative hypothesis suggests that the iron world's presence causes collisions in the debris disk that generate gas.

Source: Stuff April 04, 2019 19:18 UTC