MUSCA (Pronounced MUS-Ka)

Chart showing the constellation.

Musca, the Fly, was originally Apis the Bee, made by Bayer about 1603. Later Edmund Halley of comet fame called it Musca Apis and later still Lacaille called it Musca Australis, since simplified to Musca.

To find Musca look south late evening and find Crux, the Southern Cross. Look underneath and find the Trapezium shape of Musca. The long axis of the Southern Cross almost points at it

The most prominent feature from a dark site with a transparent sky is the Coalsack, which lies in part of Crux, Musca and Centaurus. Since the constellation lies near a bright part of the Milky Way it renders conspicuous a large irregular dark nebula called the Coal Sack. This cloud of gas and dust lies about 600 light years away. Because there are no bright hot stars nearby it does not fluoresce and glow but absorbs light. To the aborigines of Australia the Coalsack is the head of the "Emu". There is a dark rift in the Milky way going north from the Coalsack, making the neck. Look on a dark night at the dark areas, rather than the stars and bright areas.

Chart showing Musca as seen to the south at about 10 pm early May or 8 pm at the end of May.

Musca constellation

Constellation Crux Constellation Vela Constellation Carina Constellation Volans Constellation Chamaeleon Constellation Lupus Constellation Octans Constellation Apus Trianglum Australe Constellation Circinus Constellation Centaurus

Some stars and interesting objects in Musca

α Muscae is a magnitude 2.7 blue-white star 330 light years away.

β Mus is a long period binary pair of bright white stars (magnitudes 3.9 and 4.2) in a starry field. A telescope of 12.5 cm. will separate the stars on a night with good seeing.

δ Mus is a magnitude 3.6 orange giant star 180 light years away.

θ Mus is an elegant white pair, in a field sown with stars. The bright star is the second brightest Wolf-Rayet (pronounced Volf Ray-eh) binary in the sky. These rare stars have hot surfaces and appear to eject gas. Deep photographs show a faint ring nebula surrounding the star.

NGC 4372 is a globular cluster partially obscured by a long lane of dark absorbing matter, similar to the Coalsack. It is a large globular about 16,000 light years distant.

NGC 4833 was recorded by Lacaille in 1752 as resembling a small faint comet. It is, however a beautiful well resolved and fairly compact globular cluster, with small outliers scattered over and beyond it in small curved lines. It lies about 17,000 light years away.

NGC 5189 is a remarkable planetary nebula discovered by John Herschel in 1835 and described by him as 'a very strange object'. The appearance in a beautiful starry field is strongly reminiscent of a barred spiral galaxy, leading to its popular name: the "Spiral Planetary".


Musca is nearer the celestial south pole than Crux, so, like Crux, is circumpolar, that is always above the horizon, for New Zealand. The constellation is not visible from places with a latitude north of about 20° north.

The constellation is highest and due south at about 9.30 pm, NZST, in mid May.