Epoch J2000 Equinox J2000
|Right ascension||05h 18m 14.35s|
|Declination||−69° 15′ 01.10″|
|Apparent magnitude (V)||9.565 (8.6 to 11.5 (B))|
|U−B color index||–0.98|
|B−V color index||+0.11|
|Radial velocity (Rv)||+228 km/s|
|Proper motion (μ)||RA: 0.7 mas/yr
Dec.: 4.9 mas/yr
|Absolute magnitude (MV)||–9.9|
|Luminosity||1.0 × 106 L☉|
S Doradus is one of the brightest stars in the Large Magellanic Cloud, a satellite of the Milky Way. A hypergiant, it is one of the most luminous stars known (sometimes more luminous than −10 absolute magnitude), but so far away that it is invisible to the naked eye.
This star belongs to its own eponymous S Doradus class of variable stars (these classes are usually named after their prototypes); also designated as the class luminous blue variable or LBV, of which S Doradus forms the archetype. S Doradus exhibits long, slow changes in brightness, punctuated by occasional outbursts. The spectrum is variable, a typical and defining characteristic of LBVs. In its quiescent phase, it has a B type spectrum (with emission) and a temperature around 20,000K. In outburst the temperature decreases and has been observed with the spectrum of an F supergiant and a temperature below 8,000K.
S Doradus is the brightest member of the open cluster NGC 1910, visible in binoculars as a bright condensation within the main bar of the LMC.
- Høg, E. et al. (March 2000), "The Tycho-2 catalogue of the 2.5 million brightest stars", Astronomy and Astrophysics 355: L27–L30, Bibcode:2000A&A...355L..27H, doi:10.1888/0333750888/2862
- "S Dor", General Catalogue of Variable Stars (Sternberg Astronomical Institute, Moscow, Russia), retrieved 2010-11-24
- Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series 34: 1–49, Bibcode:1978A&AS...34....1N
- Evans, D. S. (June 20–24, 1966). Batten, Alan Henry; Heard, John Frederick, eds. "Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30". University of Toronto: International Astronomical Union. Bibcode:1967IAUS...30...57E.
- Lamers, H. J. G. L. M. (February 6–10, 1995), "Observations and Interpretation of Luminous Blue Variables", Proceedings of IAU Colloquium 155, Astrophysical applications of stellar pulsation, Cape Town, South Africa: Astronomical Society of the Pacific, pp. 176–191, Bibcode:1995ASPC...83..176L
- Massey, Philip (February 2000), "An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets", The Publications of the Astronomical Society of the Pacific 112 (768): 144–147, Bibcode:2000PASP..112..144M, doi:10.1086/316515