White dwarf upsets planetary system, consumes evidence

At least one poor planet — or possibly over half a dozen — is becoming a snack for the core of a dead star. A white dwarf dubbed WD 1145+017, in the constellation Virgo, hosts an orbiting trail of rocky debris, researchers report in the Oct. 22 Nature. The detritus might be all that remains of a dying solar system.

The debris cloud, detected by the Kepler space telescope, gave itself away by repeatedly blocking some starlight. Researchers also observed traces of heavy elements such as aluminum, silicon and nickel on the white dwarf. Ordinarily, these elements would sink into the star quickly and disappear, so the atoms are probably raining down on the white dwarf as the planets break apart.

The presence of heavy elements in this and other white dwarfs suggests that these dead stars periodically enjoy a planetary snack (SN: 9/24/11, p. 10).