Circinus (Pronounciation:Sir-sin-us, Abbrev:Cir, Latin:Circini) is a constellation, one of 88 constellations that the night sky is divided into. The sky is not divided up equally between the constellations. Circinus takes up 93.353 sq. degrees of the night sky which equates to 0.23% of the night sky. The constellation gets its name as it name means The Compasses . It was not one of the original constellations that had been devised by Ptolemy, instead it was created by Abbé Nicolas Louis de Lacaille years later.
Circinus is not a member of the Zodiac group of twelve constellations that appear when the Sun sets. Circinus is a southern hemispheric constellation which means it can't be seen easily or at all from the northern hemisphere.
The brightest star in Circinus is Alpha Circini. There are 4 Extrasolar Planets (Exoplanets) in this constellation that are detailed on this site. There is a dedicated page for exoplanets in Circinus. For a list of named stars, that is stars that don't start HD or HIP, please visit Circinus Star List Page.
The number of stars that have been catalogued as part of the Hipparcos Star Catalogue from Circinus is 457. The number of stars that are of magnitude 6.0 or lower in the constellation is 21. The number of stars in the constellation that make up the outline is 3.
There are no deep space objects that were identified by Charles Messier in this constellation. There are no non-Messier deep space objects in this constellation that are covered at present on this site.
The nearest star to Earth is Alpha Circini which is roughly about 54.05 Light Years from the Earth. The nearest star to the Earth with an exoplanet is HD 134060 which is about 78.94 Light Years. The furthest star that can be located in the constellation is HIP 72967 which is located about 326163.3 Light Years away from the Sun. The furthest figure is derived from either the 1997 or 2007 Hipparcos star catalogue parallax figure and it has been known to produce distances that are wrong.
The dimmest star that can be seen in Circinus with the naked eye is HD 121932. The dim star has an apparent magnitude of 5.96. The dimmest star that a person is able to see with their naked eye is 6.0 magnitude based on the table in the reference. Ref: University of Michigan
The caveat of these stars are that they are catalogued on this site. If you know of a star that is nearer or further then do let me know in the comments and I'll add it to the site. The stars mentioned are from the Hipparcos catalogue or have been added because of their special status.
It is a southern constellation and would not have problem been seen by the Greeks at the time. There is no Greek Legend behind this constellation. It was created by Abbé Nicolas Louis de Lacaille to fill in the voids in the astronomical charts.
There are no major meteor showers that radiate from within this constellation.| Name | Circinus |
| Abbreviation | Cir |
| Is a Zodiac Sign | No |
| Brightest Star | Alpha Circini |
| Area | 93.353 sq. deg. |
| Percentage of Night Sky | 0.23% |
| Size Position | 85th |
| Hemisphere | Southern |
| Site Exoplanet Count | 4 |
| Meteor Shower Count | 1 |
| Nearest Star | Alpha Circini |
| Nearest Star with Exoplanet(s) | HD 134060 |
| Dimmest Star | HD 121932 |
| Furthest Star | HIP 72967 |
| Bright Star Count | 21 |
| Hipparcos Star Count | 457 |
| Main Star Count | 3 |
| Messier Deep Space Object Count | 0 |
| *Non-Messier Deep Space Object Count | 0 |
| Bordering / Neighbouring / Surrounding Constellations | Lupus |
| Centaurus | |
| Musca | |
| Apus | |
| Triangulum Australe | |
| Norma | |
*Note: The number of Non-Messier Deep Space Object Count relates to how many are covered on this site not how many there are.
The map was generated using Night Vision, an awesome free application by Brian Simpson.