dwarf galaxy

A small elliptical or spheroidal galaxy containing between a few hundred thousand and a few million stars - far fewer than a typical galaxy. Dwarf galaxies have low luminosity and may be so loose as to resemble large open clusters of stars. Six dwarf spheroidal galaxies are known that are satellites of the Milky Way Galaxy. Their diameters range between 2 and 7 per cent of the size of the Milky Way. Dwarf ellipticals are referred to as dE galaxies.