HD 143183 is a red supergiantvariable star of spectral type M3Ia in constellationNorma. It is a member of the Norma OB1 association, at a distance of about 2 kiloparsecs. It is one of the most luminous red supergiants with a luminosity over 250,000 times greater than the Sun (L☉), and is as well one of the largest stars with a radius more than a thousand times that of the Sun (R☉).[8] Older studies frequently calculated higher luminosities and radii.[6][11] It has an estimated mass loss rate of 5×10−5M☉ per year[6] and has been once described as a cool hypergiant.[12] It is surrounded by a dozen early-type stars and a circumstellar nebula which extends 0.12 parsecs (0.39 ly).
It is possible that HD 143183 is a spectroscopic binary with an OB+ companion but this is considered doubtful.[6] HD 143183 lies approximately 1' from the 10th-magnitude O-class bright giant CD-53 6363, the second-brightest star in the cluster.
^ abcSamus, 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: B/gcvs. Bibcode:2009yCat....102025S.
^ abKlare, G.; Neckel, T. (1977). "UBV, Hβ and polarization measurements of 1660 southern OB stars". Astronomy and Astrophysics Supplement Series. 27: 215. Bibcode:1977A&AS...27..215K.
^ abHøg, E; Fabricius, C; Makarov, V. V; Urban, S; Corbin, T; Wycoff, G; Bastian, U; Schwekendiek, P; Wicenec, A (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27. Bibcode:2000A&A...355L..27H.
^ abcdefgMoffat, A. F. J. (August 1976). "Mass loss from the M 3 supergiant HD 143183 in a young compact star cluster in Norma". Astronomy and Astrophysics. 50 (3): 429–434. Bibcode:1976A&A....50..429M.
^Humphreys, R. M (1978). "Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way". The Astrophysical Journal Supplement Series. 38: 309. Bibcode:1978ApJS...38..309H. doi:10.1086/190559.