S Crucis
Variable star in the constellation Crux
From Wikipedia, the free encyclopedia
S Crucis is a star in the constellation Crux. A Cepheid variable, its apparent magnitude ranges from 6.22 to 6.92 over 4.68997 d.[2] It is a yellow-white supergiant that pulsates between spectral types F6Ib-II and G1Ib-II.[2]
Right ascension12h 54m 21.99728s[1]
Declination−58° 25′ 50.2146″[1]
Apparentmagnitude(V)6.22 - 6.92[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Crux |
| Right ascension | 12h 54m 21.99728s[1] |
| Declination | −58° 25′ 50.2146″[1] |
| Apparent magnitude (V) | 6.22 - 6.92[2] |
| Characteristics | |
| Spectral type | F6-G1Ib-II[2] |
| Variable type | δ Cep[2] |
| Astrometry | |
| Radial velocity (Rv) | −6.10[3] (−21.1 - 5.9)[4] km/s |
| Proper motion (μ) | RA: −9.480[1] mas/yr Dec.: 3.987[1] mas/yr |
| Parallax (π) | 1.0215±0.0448 mas[1] |
| Distance | 3,200 ± 100 ly (980 ± 40 pc) |
| Absolute magnitude (MV) | -3.27[5] |
| Details | |
| Radius | 37.9[6] R☉ |
| Surface gravity (log g) | 1.2 - 1.9[4] cgs |
| Temperature | 5,517 - 6,482[4] K |
| Metallicity [Fe/H] | −0.07 - 0.16[4] dex |
| Age | 116[7] Myr |
| Other designations | |
| CD−57°4766, HD 112044, HIP 62986, HR 4895, SAO 240362[8] | |
| Database references | |
| SIMBAD | data |
S Crucis is a pulsating variable star of the δ Cephei type, a Classical Cepheid variable. Its mean radius is 37.9 R☉ and that radius varies by up to 4.1 R☉ during its 4.7-day pulsation cycle.[6] Over the same cycle, the effective temperature varies between 5,517 K and 6,482 K.[4] The star is thought to be 116 million years old; it has exhausted its core hydrogen and left the main sequence.[7]