Astronomy:Pegasus Dwarf Spheroidal Galaxy

From HandWiki
Short description: Dwarf spheroidal galaxy in the constellation Pegasus
Pegasus Dwarf Spheroidal Galaxy
Andromeda VI color cutout hst 08272 04 wfpc2 f555w f450w wf sci.jpg
Hubble Space Telescope image of Pegasus Dwarf Spheroidal Galaxy
Observation data (J2000 epoch)
ConstellationPegasus
Right ascension 23h 51m 46.3s[1]
Declination+24° 34′ 57″[1]
Redshift−354 ± 3 km/s[1]
Distance2.7 ± 0.1 Mly (820 ± 20 kpc)[2][3]
Apparent magnitude (V)14.2[1]
Characteristics
TypedSph[2]
Apparent size (V)4.0 × 2.0[1]
Notable features-
Other designations
Pegasus II,[1] Andromeda VI,[1] Peg dSph,[1] KKH 99,[1] PGC 2807158

The Pegasus Dwarf Spheroidal (also known as Andromeda VI or Peg dSph for short) is a dwarf spheroidal galaxy about 2.7 million light-years away in the constellation Pegasus. The Pegasus Dwarf is a member of the Local Group and a satellite galaxy of the Andromeda Galaxy (M31).

General information

The Pegasus Dwarf Spheroidal is a galaxy with mainly metal-poor stellar populations.[4] Its metallicity is [Fe/H] ≃ −1.3.[5] It is located at the right ascension 23h51m46.30s and declination +24d34m57.0s in the equatorial coordinate system (epoch J2000.0), and in a distance of 820 ± 20 kpc from Earth and a distance of 294 ± 8 kpc[a] from the Andromeda Galaxy.

The galaxy was discovered in 1999[6] by various authors on the Second Palomar Observatory Sky Survey (POSS II) films.[7]

See also

Notes

  1. ^ For an angular distance θ between C and G, their mutual linear distance R is given by:
          R2 = D2g + D2c - 2 × Dg × Dc × cos(θ)[2]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 "NASA/IPAC Extragalactic Database". Results for Pegasus Dwarf Spheroidal. http://nedwww.ipac.caltech.edu/. 
  2. 2.0 2.1 2.2 Karachentsev, I. D.; Kashibadze, O. G. (2006). "Masses of the local group and of the M81 group estimated from distortions in the local velocity field". Astrophysics 49 (1): 3–18. doi:10.1007/s10511-006-0002-6. Bibcode2006Ap.....49....3K. 
  3. I. D. Karachentsev; V. E. Karachentseva; W. K. Hutchmeier; D. I. Makarov (2004). "A Catalog of Neighboring Galaxies". Astronomical Journal 127 (4): 2031–2068. doi:10.1086/382905. Bibcode2004AJ....127.2031K. 
  4. Van den Bergh, Sidney (May 15, 2000). The Galaxies of the Local Group. Cambridge Astrophysics. p. 240. ISBN 978-1-139-42965-8. https://books.google.com/books?id=H0JMeoqFqEcC&pg=PA240. 
  5. McConnachie, A. W.; Irwin, M. J.; Ferguson, A. M. N.; Ibata, R. A.; Lewis, G. F.; Tanvir, N. (2005). "Distances and metallicities for 17 Local Group galaxies". Monthly Notices of the Royal Astronomical Society 356 (4): 979–997. doi:10.1111/j.1365-2966.2004.08514.x. Bibcode2005MNRAS.356..979M. 
  6. Pritzl, Barton J.; Armandroff, Taft E.; Jacoby, George H.; Da Costa, G. S. (May 2005). "The Dwarf Spheroidal Companions to M31: Variable Stars in Andromeda I and Andromeda III". The Astronomical Journal 129 (5): 2232–2256. doi:10.1086/428372. Bibcode2005AJ....129.2232P. 
  7. Wallace Sargent. "The Second Palomar Observatory Sky Survey (POSS II)". Caltech. http://www.astro.caltech.edu/~wws/poss2.html. 

External links