| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Dorado |
| Right ascension | 05h 07m 34.02686s [1] |
| Declination | −63° 23′ 58.8474″ [1] |
| Apparent magnitude (V) | 5.20 - 5.32 [2] |
| Characteristics | |
| Evolutionary stage | AGB [3] |
| Spectral type | M3 III [4] |
| U−B color index | +1.85 [5] |
| B−V color index | +1.65 [5] |
| Variable type | SRb [2] |
| Astrometry | |
| Radial velocity (Rv) | 19.3±2.8 [6] km/s |
| Proper motion (μ) | RA: +13.210 mas/yr [1] Dec.: −44.813 mas/yr [1] |
| Parallax (π) | 5.6282±0.1116 mas [1] |
| Distance | 580 ± 10 ly (178 ± 4 pc) |
| Absolute magnitude (MV) | −1.00 [7] |
| Details | |
| Mass | 1.4 [8] M☉ |
| Radius | 88.3+6.6 −10.0 [9] R☉ |
| Luminosity | 1,248±47 [9] L☉ |
| Surface gravity (log g) | 0.50 [10] cgs |
| Temperature | 3,603±125 [10] K |
| Other designations | |
| 21 G. Doradus [11] , WZ Dor, CD−63°188, CPD−63°420, FK5 2389, GC 6314, HD 33684, HIP 23840, HR 1695, SAO 249198, TIC 55298910 [12] | |
| Database references | |
| SIMBAD | data |
WZ Doradus (HD 33684; HR 1695; 21 G. Doradus) is a solitary red-hued variable star [13] located in the southern constellation Dorado. It has an average apparent magnitude of 5.21, [14] making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of 580 light-years [1] and it is currently receding with a heliocentric radial velocity of 19.3 km/s . [6] At its current distance, WZ Doradus is diminished by two-tenths of a magnitude due to interstellar extinction and it has an absolute magnitude of −1.00. [7]
HD 33684 was first observed to vary in brightness by astronomer P. M. Corben in 1971. [15] It was said to have an amplitude of 0.18 magnitudes. A year later, HD 33684 was given the variable star designation WZ Doradus. [16] It was again observed in 1973 by Olin J. Eggen and he noticed that it varied within 40 days. [17] A 1998 survey found no strong emissions indicating dust around the star. [18] Another survey also found no technetium in its spectrum. [19] WZ Doradus is a semiregular variable of subtype SRb that varies between 5.2 and 5.32 within an average period of 40 days. [2] Tabur et al. (2009) found two periods for the star after it was widely believed to only have one period. [20]
| Amplitude (mag) | Period (days) |
|---|---|
| 0.042 | 26.0 |
| 0.026 | 44.6 |
WZ Doradus has a stellar classification of M3 III, [4] indicating that it is an evolved red giant. It is currently on the asymptotic giant branch, [3] generating energy via the fusion of hydrogen and helium shells around an inert carbon core. As a result of its evolved state, it has expanded to 88.3 times the radius of the Sun [9] and it now radiates 1,248 times the luminosity of the Sun [9] from its enlarged photosphere at an effective temperature of 3,603 K . [10]