Langbahn Team – Weltmeisterschaft

BL Crucis

BL Crucis

A light curve for BL Crucis, adapted from Tabur et al. (2009)[1]
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]
Distance480 ± 10 ly
(146 ± 4 pc)
Other designations
HD 108396, HIP 60781, HR 4739, SAO 239960, CD−58° 4560
Database references
SIMBADdata

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]

References

  1. ^ a b Tabur, V.; Bedding, T. R. (2009). "Long-term photometry and periods for 261 nearby pulsating M giants". Monthly Notices of the Royal Astronomical Society. 400 (4): 1945–61. arXiv:0908.3228. Bibcode:2009MNRAS.400.1945T. doi:10.1111/j.1365-2966.2009.15588.x. S2CID 15358380.
  2. ^ 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.
  3. ^ Watson, Christopher (25 August 2009). "BL Crucis". AAVSO Website. American Association of Variable Star Observers. Retrieved 20 July 2014.
  4. ^ Eggen, O. J. (June 1969). "Light Variations of Small Amplitude in the Red Giants of the Disc Population" (PDF). Information Bulletin on Variable Stars. 355. Bibcode:1969IBVS..355....1E. Retrieved 9 December 2024.
  5. ^ Kukarkin, B. V.; Kholopov, P. N.; Fedorovich, V. P.; Kireyeva, N. N.; Kukarkina, N. P.; Medvedeva, G. I.; Perova, N. B. (March 1977). "62nd Name-List of Variable Stars" (PDF). Information Bulletin on Variable Stars. 1248: 1–25. Bibcode:1977IBVS.1248....1K. Retrieved 9 December 2024.