| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Crux |
| Right ascension | 12h 27m 28.88s |
| Declination | −58° 59′ 30.4″ |
| Apparent magnitude (V) | 5.38 |
| Characteristics | |
| Spectral type | M4-5III |
| Variable type | semiregular variable |
| Astrometry | |
| Radial velocity (Rv) | 71.7 ± 0.9 km/s |
| Proper motion (μ) | RA: -20.027 ± 0.301[2] mas/yr Dec.: 3.586 ± 0.268 [2] mas/yr |
| Parallax (π) | 6.8429 ± 0.1942 mas[2] |
| Distance | 480 ± 10 ly (146 ± 4 pc) |
| Other designations | |
| Database references | |
| SIMBAD | data |
BL Crucis is a red giant and a semiregular variable in the constellation of Crux.[3] A 5th magnitude star, it is visible to the naked eye under good observing conditions. Three periods have been detected in its light curve, 30.7, 42.3 and 43.6 days.[1] It is 480 ± 10 light-years distant from Earth.[2]
In 1969, Olin J. Eggen announced that the star, then called HR 4739, is a variable star.[4] It was given its variable star designation, BL Crucis, in 1977.[5]
- ^ a b Cite error: The named reference
taburwas invoked but never defined (see the help page). - ^ a b c d Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ Cite error: The named reference
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