Andromeda IX

RA:

00 : 52.9

Dec:

+ 43 : 12

Type:

dSph

RV:

Distance:

2,900 kly

Apparent Dimension:

5 arc min

Diameter:

Brightness:

16.2 mag vis

Abs. Mag:

Mass:

Andromeda IX is a dwarf spheroidal satellite of the Andromeda Galaxy, M31; it was discovered in 2004 by resolved stellar photometry from the Sloan Digital Sky Survey (SDSS), by Zucker et.al. (2004). At the time of its discovery, it was the galaxy with the lowest known surface brightness, and the faintest galaxy known from its intrinsic absolute brightness.

Andromeda IX was found from data acquired within an SDSS scan along the major axis of M31, carried out on October 5, 2002. Its distance was estimated to be almost exactly the same as that of M31 by McConnachie et.al. (2005).

The image displayed in this page was taken from the ING archive from data acquired under the direction of Nial Tanvir et.al.. Note the very dim luminosity caused by the stars of this dwarf galaxy and the difficulty to discover it behind the foreground stars which are all members of the Milky Way galaxy.

Links:

• MPIA PR 04-06-03 on the discovery of Andromeda IX (in German)

• Daniel B. Zucker, Alexei Y. Kniazev, Eric F. Bell, David Martinez-Delgado, Eva K. Grebel, Hans-Walter Rix, Constance M. Rockosi, Jon A. Holtzman, Rene A.M. Walterbros, James Annis, Donald G. York, Zeljko Ivezic, J. Brinkmann, Howard Brewington, Michael Harvanek, Greg Hennessey, S.J. Kleinman, Jurek Krzesinski, Dan Long, Peter R. Newman, Atsuko Nitta, and Stephanie A. Snedden, 2004. Andromeda IX: A New Dwarf Spheroidal Satellite of M31. The Astrophysical Journal, Vol. 612, Issue 2, pp. L121-L124 (09/2004) [ADS: 2004ApJ...612L.121Z] -- [Preprint: astro-ph/0404268]
• A.W. McConnachie, M.J. Irwin, A.M.N. Ferguson, R.A. Ibata, G.F. Lewis, and N. Tanvir, 2005. Distances and metallicities for 17 Local Group Galaxies. Monthly Notices of the Royal Astronomical Society, Vol. 356, Issue 4, pp. 979-997 (01/2005) [ADS: 2005MNRAS.356..979M] -- [Preprint: astro-ph/0410489]

Last Modification: December 29, 2018