sentences:  L2 Puppis is most likely an asymptotic giant branch star that has passed through the main sequence and is evolving to become a white dwarf.It is shedding mass at the rate of about per year, forming a circumstellar dust disk and bipolar plumes of gas that are thought to be the start of a "butterfly"-type planetary nebula.It has been calculated that the mass of L2 Puppis is currently about and its original mass was close to about 10 billion years ago.