Pisces II (dwarf galaxy)

The Pices II dwarf galaxy ( briefly also Pisces II) is a dwarf spheroidal galaxy in the constellation of Pisces, and was discovered in 2010 in the survey of the Sloan Digital Sky Survey.

Properties

Sizes

The galaxy is located at a distance of about 180 kpc from our solar system. As a spheroidal dwarf galaxy, it has a nearly round shape with an axial ratio of 5:3 and a half-light radius of only 60 pc.

Luminosity

Pisces II is one of the smallest and faintest satellite galaxies of our Milky Way. The integral luminosity corresponds to the absolute magnitude of MV = -5m to about 10,000 times the sun. This roughly corresponds to the luminosity of an average globular cluster.

Metallicity

The stellar population of Pisces II contains mostly older stars, which originated about 10-12 billion years ago. The metallicity of these old stars is correspondingly low with [Fe / H] = -2.3, which is equivalent to that Pisces II in about 80 times less in heavy elements than the Sun has.