Pegasus Dwarf Spheroidal Galaxy

Summary

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).

Pegasus Dwarf Spheroidal Galaxy
Hubble Space Telescope image of Pegasus Dwarf Spheroidal Galaxy
Observation data (J2000 epoch)
ConstellationPegasus
Right ascension23h 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

General information edit

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 edit

Notes edit

  1. ^ For an angular distance θ between C and G, their mutual linear distance R is given by:
          R2 = D2
    g
    + D2
    c
    - 2 × Dg × Dc × cos(θ)[2]

References edit

  1. ^ a b c d e f g h i "NASA/IPAC Extragalactic Database". Results for Pegasus Dwarf Spheroidal. Retrieved 2006-11-11.
  2. ^ a b c 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. Bibcode:2006Ap.....49....3K. doi:10.1007/s10511-006-0002-6. S2CID 120973010.
  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. Bibcode:2004AJ....127.2031K. doi:10.1086/382905.
  4. ^ Van den Bergh, Sidney (May 15, 2000). The Galaxies of the Local Group. Cambridge Astrophysics. p. 240. ISBN 978-1-139-42965-8.
  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. arXiv:astro-ph/0410489. Bibcode:2005MNRAS.356..979M. doi:10.1111/j.1365-2966.2004.08514.x.
  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. arXiv:astro-ph/0501083. Bibcode:2005AJ....129.2232P. doi:10.1086/428372. S2CID 9749493.
  7. ^ Wallace Sargent. "The Second Palomar Observatory Sky Survey (POSS II)". Caltech. Archived from the original on 2009-05-16.

External links edit

  • NASA/IPAC Extragalactic Database: Pegasus Dwarf Spheroidal
  • Armandroff, Jacoby, & Davies, "Low Surface Brightness Galaxies around M31", Astrophys. J. 118, 1220-1229 (1999).