KW Sagittarii

KW Sagittarii
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Sagittarius
Right ascension 17h 52m 00.7257s[1]
Declination −28° 01′ 20.562″[1]
Apparent magnitude (V) 8.983 (v)[1]
8.5 to 11 (AAVSO)
11.0 to 13.2 (p)[2]
Characteristics
Spectral type M1.5Iab:[1]
B−V color index 2.5[1]
Variable type SRC[2]
Details
Radius 1,460[3] R☉
Surface gravity (log g) −0.5[3]
Luminosity (bolometric) 360,000[3] L☉
Temperature 3,700[3] K
Astrometry
Proper motion (μ) RA: −1.11[1] mas/yr
Dec.: −1.76[1] mas/yr
Distance ~10,000[4][5] ly
(~3,000[4][5] pc)
Other designations
KW Sgr, CD−27 12032, HD 316496, HIP 87433.[1]
Database references
SIMBAD data

KW Sagittarii is a red supergiant, located approximately 10,000 light-years away from our Sun in the direction of the constellation Sagittarius. Its diameter is 1460 solar diameters, making it one of the largest known stars. Its bolometric luminosity is 360,000 times the Sun's.[3]

See also

References

  1. ^ a b c d e f g h V* KW Sgr -- Semi-regular pulsating Star, database entry, SIMBAD. Accessed on line November 10, 2010.
  2. ^ a b KW Sgr, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line November 10, 2010. (Quick look: KW+Sgr)
  3. ^ a b c d e Table 4, Levesque et al. 2005, using Mbol = −9.15 for KW Sagittarii (see the table) and 4.74 for the Sun (p. 982.)
  4. ^ a b KW Sagittarii is in the Sgr OB5 association, which has an estimated distance modulus of 12.4. See Tables 1 and 2, Levesque et al. 2005.
  5. ^ a b "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not As Cool As We Thought", Emily M. Levesque, Philip Massey, K. A. G. Olsen, Bertrand Plez, Eric Josselin, Andre Maeder, and Georges Meynet, The Astrophysical Journal 628, #2 (August 2005), pp. 973-985, doi:10.1086/430901, Bibcode: 2005ApJ...628..973L.

External links

Stars of Sagittarius
Bayer
Flamsteed
Nearby
Other