A long-standing problem in understanding the evolution of stars has been determining the nature of the stellar progenitors for white dwarf stars. In particular, astronomers want to know how a rather massive star (up to seven times the mass of the Sun) can lose enough mass to become a white dwarf. Key questions include: Which main-sequence stars eventually end their life as white dwarfs? How much mass do they lose in late evolutionary stages? What process allows this to occur?

Embargoed until 1:00 pm Eastern (8:00 am HST) January 12, 2005

December 31, 2005