Tags: Star.
HL Tau 76 is a variable white dwarf star of the DAV (or ZZ Ceti) type. It was observed by G. Haro and W. J. Luyten in 1961 and was the first variable white dwarf discovered when in 1968 Arlo U. Landolt found that it varied in brightness with a period of approximately 749.5 seconds or 12.5 minutes. Like other DAV white dwarfs its variability arises from non-radial gravity wave pulsations within itself. § 7.