Musca
The pattern of the brightest stars resembles that of Ursa Minor, in that the stars form a pattern reminiscent of a bowl with a handle. Lying south-southeast of Acrux in neighbouring Crux is Alpha Muscae. It is the brightest star in the constellation with an apparent magnitude of 2.7. Lying around 310 light-years away, it is a blue-white star of spectral type B2IV-V that is around 4520 times as luminous and 8 times as massive as the Sun. The star is a Beta Cephei variable with about 4.7 times the Sun's diameter, and pulsates every 2.2 hours, varying by 1% in brightness. A nearby star of magnitude 13 may or may not be a companion star. Marking the fly's tail is Gamma Muscae, a blue-white star of spectral type B5V that varies between magnitudes 3.84 and 3.86 over a period of 2.7 days. It is a variable of a different type, classed as a slowly pulsating B star, a type of variable. It is around five times as massive as our Sun.
Crux
Crux is a constellation located in the southern sky in a bright portion of the Milky Way. It is among the most easily distinguished constellations, as all of its four main stars have an apparent visual magnitude brighter than +2.8, even though it is the smallest of all 88 modern constellations. Its name is Latin for cross, and it is dominated by a cross-shaped or kite-like asterism that is commonly known as the Southern Cross.
Predominating is the first-magnitude blue-white star of Alpha Crucis or Acrux, being the constellation's brightest and most southerly member. Crux is followed by four dominant stars, descending in clockwise order by magnitude: Beta, Gamma (one of the closest red giants to Earth), Delta and Epsilon Crucis. Many of these brighter stars are members of the Scorpius–Centaurus Association, a large but loose group of hot blue-white stars that appear to share common origins and motion across the southern Milky Way. The constellation contains four Cepheid variables that are each visible to the naked eye under optimum conditions. Crux also contains the bright and colourful open cluster known as the Jewel Box (NGC 4755) and, to the southwest, partly includes the extensive dark nebula, known as the Coalsack Nebula.