Delta Cancri
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 44m 41.099s |
| Declination | +18° 09′ 15.51″ |
| Apparent magnitude (V) | +3.94 |
| Characteristics | |
| Spectral type | K0 III |
| U−B color index | +0.99 |
| B−V color index | +1.08 |
| Astrometry | |
| Radial velocity (Rv) | 16.39±0.25 km/s |
| Proper motion (μ) | RA: −18.435 mas/yr Dec.: −227.813 mas/yr |
| Parallax (π) | 23.8271±0.1853 mas |
| Distance | 137 ± 1 ly (42.0 ± 0.3 pc) |
| Absolute magnitude (MV) | +0.843 |
| Details | |
| Mass | 1.71 M☉ |
| Radius | 11.7±0.13 R☉ |
| Luminosity | 59.5±1.4 L☉ |
| Surface gravity (log g) | 2.59 cgs |
| Temperature | 4684±27 K |
| Metallicity [Fe/H] | −0.03 dex |
| Rotational velocity (v sin i) | 2.8 km/s |
| Age | 2.45 Gyr |
| Other designations | |
| Asellus Australis, δ Cnc, 47 Cnc, BD+18°2027, FK5 326, GC 12022, HD 74442, HIP 42911, HR 3461, SAO 98087, ADS 6967, CCDM 08447+1809 | |
| Database references | |
| SIMBAD | data |
Delta Cancri (δ Cancri, abbreviated Delta Cnc, δ Cnc) is a double star about 140 light-years from the Sun in the constellation of Cancer.
Its two main constituents are designated Delta Cancri A and B. A is itself a binary star whose components are Delta Cancri Aa (formally named Asellus Australis /əˈsɛləs ɔːsˈtreɪlɪs/, the traditional name of the entire system) and Ab.
The star system is 0.08 degree north of the ecliptic, so it can be occulted by the Moon and more rarely by planets; it is occulted (eclipsed) by the sun from about 31 July to 2 August. Thus the star can be viewed the whole night, crossing the sky at the start of February.