Coma Berenices (dwarf galaxy)

[2][4] It is classified as a dwarf spheroidal galaxy (dSph) meaning that it has an elliptical (ratio of axes ~ 5:3) shape with the half-light radius of about 70 pc.

A high mass to light ratio implies that Com is dominated by the dark matter.

[4] The stellar population of Com consists mainly of old stars formed more than 12 billion years ago.

[2] The metallicity of these old stars is also very low at [Fe/H] ≈ −2.53±0.45, which means that they contain 350 times less heavy elements than the Sun.

The measurements have so far failed to detect any neutral hydrogen in it—the upper limit is only 46 solar masses.