MB3 is a dwarf spheroidal galaxy discovered in 1997 and located about 10 million

light-year A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

s away from the Earth. It was discovered during an optical survey of the IC 342/Maffei group to which the galaxy is a member. MB3 is a companion galaxy of

Dwingeloo 1 Dwingeloo 1 is a barred spiral galaxy about 10 million light-years away from the Earth, in the constellation Cassiopeia. It lies in the Zone of Avoidance and is heavily obscured by the Milky Way. The size and mass of Dwingeloo 1 are comparabl ...

and situated in the

Zone of Avoidance The Zone of Avoidance (ZOA, ZoA), or Zone of Galactic Obscuration (ZGO), is the area of the sky that is obscured by the Milky Way. The Zone of Avoidance was originally called the Zone of Few Nebulae in an 1878 paper by English astronomer Richard ...

. MB 3 is thought to be a member of the

IC 342/Maffei Group The IC 342/Maffei Group (also known as the IC 342 Group or the Maffei 1 Group) corresponds to one or two galaxy groups close to the Local Group. The member galaxies are mostly concentrated around either IC 342 or Maffei 1, which would be the brig ...

, a galaxy group adjacent to the Local Group. The visible diameter of MB 3 is approximately 1.9′, which at the distance of 3 Mpc corresponds to about 2 kpc. In optical images it appears as a highly flattened diffuse oval located approximately 9.2′ to the southwest of Dwingeloo 1. No neutral or molecular hydrogen has been detected in it, which is consistent with its classification as a dwarf spheroidal galaxy.

References

{{Reflist, 2, refs= {{Cite journal , last1 = McCall , first1 = M. L. , last2 = Buta , first2 = R. J. , doi = 10.1086/118314 , title = Discovery of a Second Companion of Dwingeloo 1 , journal = The Astronomical Journal , volume = 113 , pages = 981 , year = 1997 , bibcode = 1997AJ....113..981M {{cite web , title=NASA/IPAC Extragalactic Database , work=Results for MB3 , url=http://nedwww.ipac.caltech.edu/ , access-date=2011-10-24 {{Cite journal , last1 = Buta , first1 = R. J. , last2 = McCall , first2 = M. L. , doi = 10.1086/313255 , title = The IC 342/Maffei Group Revealed , journal = The Astrophysical Journal Supplement Series , volume = 124 , pages = 33–93 , year = 1999 , issue = 1 , bibcode = 1999ApJS..124...33B

External links

Dwingeloo 2 – Galaxy
Dwarf galaxies IC 342/Maffei Group Astronomical objects discovered in 1997 166069 Cassiopeia (constellation)