Or Wasting Away in Eridani-ville, Searching for my lost stellar mass.
Astronomers at the Gemini Observatory have discovered an unusual binary star system in the constellation Eridanus. EF Eridani is a 17th magnitude white dwarf with a close stellar companion. In fact the pair is a cataclysmic variable: the dense white dwarf completely depleted its stellar companion, eating nearly the entire mass of the companion star. The white dwarf consumed so much of the companion star it can no longer sustain nuclear fusion and it has degenerated into a worn out brown dwarf, roughly the size of Jupiter.
Ages ago, the companion was presumably a normal star that began overflowing its gravitational domain in the binary and spilling a stream of matter onto the white dwarf, which probably blew it off in a series of nova outbursts. Now the system has almost reached the dead-end state that many cataclysmic binaries will finally settle into â€” when the donor star gets whittled down to substellar mass, ceases generating heat to drive the transfer of mass, and is left hanging in a fast, close orbit as it cools.
Cool, it’s a vampire star system. “I vant to suck your hydrogen, blah, blah.”