The radial velocity of V382 Carinae has long been known to be variable, but variations in its brightness were unclear. Brightness variations were detected by some observers, but others found it to be constant.[12] It was formally named as a variable star in 1981, listed in the
General Catalogue of Variable Stars as a possible
δ Cephei variable.[13][3] It has been described as a pseudo-Cepheid, a supergiant with pulsations similar to a Cepheid but less regular.[10]
Analysis of
Hipparcos photometry showed clear variation with a maximum range of 0.12 magnitudes and the star was treated as an
α Cygni variable. A period of 556 days was suggested, but it is not entirely consistent.[14] It is now generally treated as a
semiregular or
irregular supergiant.[10][5]
Properties
V382 Carinae
V382 Car is the brightest yellow hypergiant in the night sky, easily visible to the naked eye and brighter than
Rho Cassiopeiae although not visible from much of the northern hemisphere. It is 6,200
light years from
Earth and around 500 times the radius of the
Sun.[9] The large size means that V382 Car is over 200,000 times as luminous as the sun. The low
infrared excess suggest that V382 Carinae may be cooling towards a red supergiant phase, less common than yellow hypergiants evolving towards hotter temperatures.[4][15]
^
abcDucati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237.
Bibcode:
2002yCat.2237....0D.
^
abSamus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1.
Bibcode:
2009yCat....102025S.
^
abWatson, C. L. (2006). "The International Variable Star Index (VSX)". The Society for Astronomical Sciences 25th Annual Symposium on Telescope Science. Held May 23–25. 25: 47.
Bibcode:
2006SASS...25...47W.
^
abcdUsenko, I. A.; Kniazev, A. Yu.; Berdnikov, L. N.; Kravtsov, V. V. (2011). "Spectroscopic studies of Cepheids (S Cru, AP Pup, AX Cir, S TrA, T Cru, R Mus, S Mus, U Car) and semiregular bright supergiants (V382 Car, HD 75276, R Pup) in the southern hemisphere". Astronomy Letters. 37 (7): 499.
Bibcode:
2011AstL...37..499U.
doi:
10.1134/S1063773711070061.
S2CID122968535.
^Kholopov, P. N.; Samus', N. N.; Kukarkina, N. P.; Medvedeva, G. I.; Perova, N. B. (1981). "65th Name-List of Variable Stars". Information Bulletin on Variable Stars. 1921: 1.
Bibcode:
1981IBVS.1921....1K.