Epsilon Muscae, Latinized as ε Muscae, is a red giant star of spectral type M5III in the constellation Musca. Originally a main-sequence star of around 2 solar masses, it is now on the asymptotic giant branch and has now expanded to 117 times the Sun's diameter and 1,700 its luminosity. It is a semiregular variable, varying between visual magnitudes 4.0 and 4.3 in eight distinct periods ranging from a month to over half a year in length. It is located around 326 light-years distant, the same distance as the Lower Centaurus–Crux subgroup of the Scorpius–Centaurus association, although it is moving much faster at around 100 km/s and does not share a common origin.