We report the discovery of a new dwarf galaxy , Andromeda XXVIII , using data from the recently-released SDSS DR8 .
The galaxy is a likely satellite of Andromeda , and , at a separation of 365 ^ { +17 } _ { -1 } kpc , would be one of the most distant of Andromeda ’ s satellites .
Its heliocentric distance is 650 ^ { +150 } _ { -80 } kpc , and analysis of its structure and luminosity show that it has an absolute magnitude of M _ { V } = -8.5 ^ { +0.4 } _ { -1.0 } and half-light radius of r _ { h } = 210 ^ { +60 } _ { -50 } pc , similar to many other faint Local Group dwarfs .
With presently-available imaging we are unable to determine if there is ongoing or recent star formation , which prevents us from classifying it as a dwarf spheroidal or dwarf irregular .