Z Chamaeleontis (abbreviated Z Cha) is a dwarf nova variable star system approximately 394 light-years away from the Sun, where two stars orbit each other every 1.78 hours. The system comprises an eclipsing white dwarf and red dwarf and possibly a yet unconfirmed third low-mass substellar companion.
Z Chamaeleontis was discovered in 1904, during the work required to produce the Astrographic Catalogue. By 1905 a period of variability had been derived. in 1969, George S. Mumford discovered that in addition to being a dwarf nova, the star is an eclipsing variable.
Substellar companion
Dai et al. (2009) invoke the presence of a third object to explain orbital period variations with an apparent periodicity of roughly 28 years. The third body could yield a minimum mass 20 times greater than Jupiter and be located 9.9 Astronomical Units away from the dwarf nova, being likely a low-mass brown dwarf.
See also HW Virginis NN Serpentis OY Carinae
References