Located in the southern hemisphere, Corona Australis is a constellation that translates to “southern crown” from Latin. The constellation is the southern counterpart of Corona Borealis, the northern crown. It is one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, as the Ancient Greeks saw Corona Australis as a wreath rather than a crown and associated it with Sagittarius or Centaurus. Other cultures have likened the pattern to a turtle, ostrich nest, a tent, or even a hut belonging to a rock hyrax.

The 2 brightest stars in the constellation are Alpha and Beta Coronae Australis, which have apparent magnitudes of around 4.1. Corona Australis contains one of the closest star-forming regions to the Solar System, which is the dusty dark nebula known as the Corona Australis Molecular Cloud. It is located about 430 light years from the Milky Way,

Corona Australis culminates on the June 30th, but only covers 128 square degrees. This makes Corona Australis the 80th largest constellation, but is only visible at latitudes south of 53° north.

	Applicable Information
Visibility In Pacific Northwest	Barely Visible In Southern Horizon May to August
Best Times To View	June
Right Ascension	17h 58m 30.1113s–19h 19m 04.7136s
Declination	−36.7785645°–−45.5163460°
Area	128 square degrees
Main Stars	6
Brightest Object	α CrA
Meteor showers	Corona Australids
Messier objects	0
Neighboring Constellations	Sagittarius, Scorpius, Ara, Telescopium

History

Corona Australis may have been recorded by ancient Mesopotamians in the MUL.APIN, as a constellation called MA.GUR. This translates to “The Bark.”

In the 3rd century BC, the Greek poet Aratus wrote of, but did not name the constellation, instead calling the two crowns Στεφάνοι (Stephanoi). The Greek astronomer Ptolemy described the constellation in the 2nd century AD, though with the inclusion of Alpha Telescopii, since transferred to Telescopium.

Corona Australis has been associated with the myth of Bacchus and Stimula. After Bacchus, became an adult and the god of wine, he honored his deceased mother by placing a wreath in the sky. This wreath was what is now known as Coronis Australis.

In Chinese astronomy, the stars of Corona Australis are located within the Black Tortoise of the North. The constellation itself was known as ti’en pieh or the “Heavenly Turtle” and during the Western Zhou period, marked the beginning of winter. 

Arabic names for Corona Australis include Al Ķubbah “the Tortoise”, Al Ĥibā “the Tent” or Al Udḥā al Na’ām “the Ostrich Nest”.

The ǀXam speaking San people of South Africa knew the constellation as ≠nabbe ta !nu “house of branches”, which was owned originally by the Dassie, and the star pattern depicting people sitting in a semicircle around a fire.

The indigenous Boorong people of northwestern Victoria saw it as Won, a boomerang thrown by Totyarguil, which was Altair. 

The Aranda people of Central Australia saw Corona Australis as a coolamon carrying a baby, which was accidentally dropped to earth by a group of sky-women dancing in the Milky Way.

The Torres Strait Islanders saw Corona Australis as part of a larger constellation encompassing part of Sagittarius and the tip of Scorpius’s tail.

Stars

Although Corona Australis is not a bright constellation, it is distinctive because of its easily identifiable pattern of stars. This identifiable star pattern has been described by observers as a horseshoe or oval-shaped. There are no stars brighter than 4th magnitude, but the constellation still has 21 stars visible to the unaided eye. This means that these 21 stars are brighter than magnitude 5.5.

Nicolas Louis de Lacaille used the Greek letters Alpha to Lambda for labelling the most prominent eleven stars in the constellation. Mu Coronae Australis was labelled later by Johann Elert Bode and retained by Benjamin Gould, who deemed it bright enough to warrant naming.

In the north of the constellation is the Corona Australis Molecular Cloud, a dark molecular cloud with many embedded reflection nebulae, which is a star-forming region. It is one of the closest star-forming regions to the Solar System.

Objects in the molecular cloud includes NGC 6729, NGC 6726, NGC 6727, and IC 4812. These objects were first recorded by Johann Friedrich Julius Schmidt in 1865.

The Coronet cluster, about 554 light years away at the edge of the Gould Belt, is also used in studying star and protoplanetary disk formation.

Near Epsilon and Gamma Coronae Australis is Bernes 157, which means it is a dark nebula and star forming region. It is a large nebula, 55 by 18 arcminutes, that possesses several stars around magnitude 13.

IC 1297 is a planetary nebula of apparent magnitude 10.7, which appears as a green-hued roundish object in higher-powered amateur instruments.

Corona Australis’ location near the Milky Way means that galaxies are uncommonly seen. NGC 6768 is a magnitude 11.2 object that is made up of two galaxies merging. 1 of these merging galaxies is an elongated elliptical galaxy of classification E4 and the other a lenticular galaxy of classification S0.

IC 4808 is a galaxy of apparent magnitude 12.9 located on the border of Corona Australis with the neighboring constellation of Telescopium and 3.9 degrees west-southwest of Beta Sagittarii. Amateur telescopes will only show a suggestion of its spiral structure, but the central area of the galaxy does appear brighter.

Make sure to check out other articles on the site, including a brief introduction to constellations, other constellation articles, and more!