Var 83
Luminous blue variable star in the constellation Triangulum
title: "Var 83" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["stars-in-the-triangulum-galaxy", "triangulum", "triangulum-galaxy", "extragalactic-stars", "luminous-blue-variables"] description: "Luminous blue variable star in the constellation Triangulum" topic_path: "science/astronomy" source: "https://en.wikipedia.org/wiki/Var_83" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Luminous blue variable star in the constellation Triangulum ::
|image=[[File:Var83.jpg|240px]]
|caption=Location of Var 83 (circled in green) within M33
|epoch= J2000
|constell=Triangulum
|ra=
|dec=
|appmag_v=15.4-16.6
|type=LBV
|class=LBV
|r-i =
|v-r =
|b-v =+0.1
|u-b =−0.9
|variable=LBV
|radial_v=
|prop_mo_ra=+11.54
|prop_mo_dec=−2.75
|parallax=
|p_error=
|dist_ly=~3,000,000
|dist_pc=~900,000
|absmag_v= −8.4- −9.5
|radius=150
|luminosity=2,100,000-4,500,000
|temperature=18,000-37,000
|metal=
|gravity=
|rotation=
|age=
| names =M33 Var 83, VHK 83, 2MASS J01341090+3034373
| Simbad=VHK+83
VHK 83 (Var 83 in the VHK survey) is a luminous blue variable (LBV) in the constellation Triangulum, in the Triangulum Galaxy. With its bolometric luminosity of at least 2,240,000 times that of the Sun (4,500,000 in some estimates), it was described as "the brightest nonstable star in M33" and is one of the most luminous stars known.
The brightness varies slowly and unpredictably over a 1-2 magnitude visual range and can remain approximately constant for many years. These variations, combined with the high luminosity and temperature of the star, caused it to be grouped with the Hubble-Sandage variables even before the term "Luminous blue variable" was more than a simple description. Despite widespread agreement that it is an LBV, it has yet to be observed in outburst, although the temperature has been observed to change in tandem with the brightness variations.
Temperature estimates for the star range from around to well over . The hotter temperatures found from fitting the spectral energy distribution (SED) are consistent with the calculated luminosity of an LBV in the quiescent stage, but the spectrum is that of a cooler star.
References
References
- {{cite constellation. VHK 83
- (2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues.
- (1984). "IUE and ground-based observations of the Hubble-Sandage variables in M31 and M33". The Astrophysical Journal.
- (2006). "LBVs in M33: Their Environments and Ages". Stellar Evolution at Low Metallicity: Mass Loss.
- (2014). "Luminous and Variable Stars in M31 and M33. II. Luminous Blue Variables, Candidate LBVS, Fe II Emission Line Stars, and Other Supergiants". The Astrophysical Journal.
- (2004). "The Pul-3 catalogue of 58483 stars in the Tycho-2 system". Astronomy and Astrophysics.
- (2009). "A new luminous variable in M33". Monthly Notices of the Royal Astronomical Society: Letters.
- (1975). "A survey of bright variable stars in M33". The Astrophysical Journal Supplement Series.
- (1978). "Luminous variable stars in M31 and M33". The Astrophysical Journal.
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