List of Triangulum's suspected satellite galaxies
The Triangulum subgroup is made up of the Triangulum Galaxy (M33) and its satellites. Although Triangulum does not have any proven satellite galaxies, a number of galaxies are suspected of being in the system.
Andromeda XXII is located much closer in projection to M33 than M31 (42 kiloparsecs (140 kly) vs. 224 kiloparsecs (730 kly)). This fact suggests that it might be the first Triangulum (M33) satellite ever discovered. However, it is currently catalogued as a satellite of Andromeda (M31).
Andromeda II is a dwarf spheroidal galaxy about 2.22 Mly away in the constellation Andromeda. It is part of the Local group of galaxies and is a satellite galaxy of the Andromeda Galaxy (M31) but it's also situated closely to the Triangulum Galaxy (M33), it is not quite clear if it is a satellite of the one or the other galaxy.
|Name||Type||Distance from Sun
|Triangulum I (Andromeda XXII)||2009|
- Nicolas F. Martin, Alan W. McConnachie, Mike Irwin, Lawrence M. Widrow, Annette M. N. Ferguson, Rodrigo A. Ibata, John Dubinski, Arif Babul, Scott Chapman, Mark Fardal, Geraint F. Lewis, Julio Navarro, R. Michael Rich; "PAndAS' cubs: discovery of two new dwarf galaxies in the surroundings of the Andromeda and Triangulum galaxies"; The Astrophysical Journal, Volume 705, Issue 1, pp. 758-765 (2009); doi:10.1088/0004-637X/705/1/758; Bibcode: 2009ApJ...705..758M; arXiv:0909.0399;
- 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.