Z Chamaeleontis
| Observation data Epoch {{{epoch}}} Equinox | |
|---|---|
| Constellation | Chamaeleon |
| Right ascension | 08h 07m 27.75s |
| Declination | −76° 32′ 00.7″ |
| Apparent magnitude (V) | +13.0 |
| Characteristics | |
| Spectral type | DA / M6V |
| Astrometry | |
| Distance | 316.2 ly (97 pc) |
| Details | |
| Mass | 0.7/0.12 M☉ |
| Radius | 0.013/0.48 R☉ |
| Luminosity | 0.007/0.017 L☉ |
| Temperature | 14,700/3100 K |
| Orbit | |
| Period (P) | 0.0002 yr |
| Semi-major axis (a) | 0.003 Astronomical Units" |
| Inclination (i) | 81.7° |
| Other designations | |
Z Cha, 2E 1942, SBC9 505, CSV 1244, 2MASS J08072774-7632006, SON 4893, 2E 0808.8-7622, 1RXS J080728.8-763157, AAVSO 0809-76 | |
| Database references | |
| SIMBAD | data |
Z Chamaeleontis (abbreviated Z Cha) is an dwarf nova variable star system approximately 316 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.[1]
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.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b (unconfirmed) | ≥20 MJ | 9.9 | 28 | ≤0.2 | — | — |
See also
References
- 1 2 Dai; Qian, Shengbang; Lajús, Eduardo FernáNdez (2009). "Evidence of a Brown Dwarf in the Eclipsing Dwarf Nova Z Chamaeleonis". The Astrophysical Journal. 703 (1): 109–113. Bibcode:2009ApJ...703..109D. doi:10.1088/0004-637X/703/1/109.
Coordinates: 
08h 07m 27.75s, −76° 32′ 00.7″
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