Andromeda XXII (Pisces VI, Triangulum I) is a low
surface brightness
In astronomy, surface brightness (SB) quantifies the apparent brightness or flux density per unit angular area of a spatially extended object such as a galaxy or nebula, or of the night sky background. An object's surface brightness depends on ...
dwarf spheroidal galaxy about away from the
Sun in the
constellation Pisces
Pisces may refer to:
* Pisces, an obsolete (because of land vertebrates) taxonomic superclass including all fish
*Pisces (astrology), an astrological sign
*Pisces (constellation), a constellation
**Pisces Overdensity, an overdensity of stars in t ...
, of the
Local Group
The Local Group is the galaxy group that includes the Milky Way.
It has a total diameter of roughly , and a total mass of the order of .
It consists of two collections of galaxies in a "dumbbell" shape: the Milky Way and its satellites form ...
.
Andromeda XXII is located much closer in projection to M33 than M31
vs. This fact suggests that it might be the first
Triangulum
Triangulum is a small constellation in the northern sky. Its name is Latin for " triangle", derived from its three brightest stars, which form a long and narrow triangle. Known to the ancient Babylonians and Greeks, Triangulum was one of the 4 ...
(M33) satellite ever discovered. However, it is currently catalogued as a satellite of
Andromeda (M31).
[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
''The Astrophysical Journal'', often abbreviated ''ApJ'' (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and Ja ...
, Volume 705, Issue 1, pp. 758-765 (2009); ; ; ;
The discovery arose from the first year data of a
photometric survey Photometry can refer to:
* Photometry (optics), the science of measurement of visible light in terms of its perceived brightness to human vision
* Photometry (astronomy), the measurement of the flux or intensity of an astronomical object's electrom ...
of the
M31/
M33 subgrouping of the Local Group by the
Pan-Andromeda Archaeological Survey
Pan-Andromeda Archaeological Survey (PAndAS) is a large-scale astronomical survey using the Canada-France-Hawaii Telescope.
The survey is exploring the structure and content of the Andromeda Galaxy (M31) and its neighbour, the Triangulum Galaxy ( ...
(PAndAS). This survey was conducted with the Megaprime/MegaCam wide-field camera mounted on the
Canada-France-Hawaii Telescope.
See also
*
Low surface brightness galaxy
A low-surface-brightness galaxy, or LSB galaxy, is a diffuse galaxy with a surface brightness that, when viewed from Earth, is at least one magnitude lower than the ambient night sky.
Most LSBs are dwarf galaxies, and most of their baryonic mat ...
(LSB galaxy)
*
Dwarf spheroidal galaxy (dSph)
*
Satellite galaxy
*
Triangulum Galaxy
The Triangulum Galaxy is a spiral galaxy 2.73 million light-years (ly) from Earth in the constellation Triangulum. It is catalogued as Messier 33 or NGC (''New General Catalogue)'' 598. With the D25 isophotal diameter of , the Triangulum Galax ...
*
Andromeda Galaxy
The Andromeda Galaxy (IPA: ), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula, is a barred spiral galaxy with the diameter of about approximately from Earth and the nearest large galaxy to the Milky Way. The gal ...
*
Pisces constellation
Pisces is a constellation of the zodiac. Its vast bulk – and main asterism viewed in most European cultures per Greco-Roman antiquity as a distant pair of fishes connected by one cord each that join at an apex – are in the Northern ...
References
{{Andromeda galaxy
Dwarf spheroidal galaxies
Local Group
Andromeda Subgroup
Pisces (constellation)