CORONA AUSTRALIS, pronounced koh-ROH-nah ass-TRAY-liss,
TELESCOPIUM, pronounced TEL-ah SKOH-pee-um,
ARA, pronounced AY-rah
Corona Australis, the Southern Crown, was included in Ptolemy's 48 constellations, and assigned 13 stars. In one legend it is said to represent the crown worn by the centaur Sagittarius - a nearby grouping of stars. Although faint, it is a noticeable figure, situated on the edge of the Milky Way.
Telescopium, the Telescope, was originally Tuba Astronomicus, and invented by the Frenchman Lacaille, to honour the important instrument. It is a faint and contrived constellation, but its three principal stars form with θ Ara a small quadrilateral immediately south of Corona Australis. This is in the extreme north-west corner, with the rest of the constellation containing only insignificant stars.
Ara, the Altar, appears amongst the 48 constellations of Ptolemy as the tripod censer, having seven stars. This relatively faint and little known constellation, sometimes visualised as the altar on which Centaurus the Centaur, was about to sacrifice Lupus, the Wolf, or the Altar of the Gods, lies immediately south of Scorpius' tail. The Milky Way is rich and bright in this region, and is in places obscured by dark nebulae.
To find these constellations, look high in the north evening sky to find the tail of Scorpius. The Southern Crown should be readily apparent, especially away from City lights.
Some stars and interesting objects in the Constellations
α Corona Australis is a white star, magnitude 4.1 and 100 light years away.
β CrA is a magnitude 4.1 yellow giant star 110 light years away.
γ CrA is a double star with a period of 122 years. The pair of 5th magnitude yellow stars are currently near their minimum separation and a telescope with greater than 100 mm aperture is needed to split the stars.
κ CrA is a pair of 6th magnitude blue-white stars easily seen in small telescopes. The pair lie about 460 light years away.
NGC 6541 is a 6th magnitude globular cluster about 25,000 light years away, visible in binoculars or small telescopes. Its well condensed appearance in its starry field is most beautiful.
α Telescopii is a magnitude 3.5 blue-white star 590 light years away.
δ Tel consists of two blue-white stars of magnitudes 5.0 and 5.1 visible separately in binoculars and telescopes. They are unrelated stars, being at 590 and 720 light years away.
ε Tel is a magnitude 4.5 yellow giant star 190 light years away.
ζ Tel is a magnitude 4.1 yellow giant star 170 light years away.
NGC 6584 is a conspicuous but not bright globular cluster, visible easily as a faint haze in small telescopes.
α Arae is a blue-white star magnitude 3.0, lying about 220 light years away.
β Ara is a magnitude 2.9 yellow supergiant star 780 light years away.
γ Ara is magnitude 3.3 blue-white giant star 1100 light years away.
δ Ara is magnitude 3.6 blue-white star 150 light years away.
ζ Arae is a magnitude 3.1 orange giant star 140 light years away.
NGC 6193 is a bright open cluster of about 30 stars, A wide field telescope well shows the remarkable curved chains and lobes of stars, with a small group near the centre. Associated with the cluster is the emission nebula NGC 6188. This needs a clear, dark night and good aperture. An OIII filter helps.
NGC 6397 is a large and bright globular cluster easily visible with binoculars or a small telescope. It has a well condensed centre; there are orange stars in it, and some of the outliers are in arcs and sprays. It is one of the best clusters for small telescopes, and faintly visible to the unaided eye in a dark sky. The cluster is one of the nearest to the Sun at about 7000 light years.
Corona Australis passes almost directly overhead as seen from New Zealand. At the beginning of August it is highest in the sky about 11pm, by 10pm mid August and 9pm at the end of August. Telescopium is to the south of Corona Australis, that is towards the pole, while Ara is to the west of Telescopium. Both the latter constellations are circumpolar from the south of New Zealand, that is they never set, while Corona Australis only sets for 3 or 4 hours.