Constellation, Cir
Circinus: the Drawing Compass
Circinus covers 93 square degrees of sky, the 85th largest of the 88. Its brightest star is star HIP 71908. It is best placed in the evening sky in June.
Circinus at a glance
| Fact | Value |
|---|---|
| IAU abbreviation | Cir |
| Meaning | the Drawing Compass |
| Pronounced | SER-sin-us |
| Genitive, used in star names | Circini (for example a Bayer name such as α Circini) |
| Area | 93 square degrees, number 85 of 88 by size |
| Stars to magnitude 6 in our catalogue | 21 |
| Brightest star | star HIP 71908, magnitude 3.2 |
| Best seen | Evenings in June, when it is highest at 9 pm |
| Declination range | -70° to -56° |
| Borders | Triangulum Australe, Centaurus, Musca, Norma, Apus, Lupus |
Where on Earth you can see Circinus
Circinus spans declinations -70° to -56°. Every part of it rises above the horizon at some moment for observers between latitudes 90°S and 20°N. Some of it can be seen from latitudes 90°S to 34°N. South of 34°S none of it ever sets. This is geometry only: it ignores haze, hills and buildings near the horizon.
From six cities
| City | Latitude | Visibility | Middle at its highest |
|---|---|---|---|
| Pune | 18.5°N | All of it rises | 8° |
| New York | 40.7°N | Never rises | below the horizon |
| London | 51.5°N | Never rises | below the horizon |
| Tromsø | 69.6°N | Never rises | below the horizon |
| Tokyo | 35.7°N | Never rises | below the horizon |
| Sydney | 33.9°S | All of it rises | 60° |
Circinus's named stars
None of the stars brighter than magnitude 6 in Circinus has a name approved by the IAU Working Group on Star Names.
How these facts were found
The name, meaning and boundaries are the IAU's. Area, borders and the latitude ranges are computed from those boundaries; the brightest star and the star count come from a magnitude-6 star catalogue; star names are matched to the catalogue by Hipparcos number and checked by position. The month is when Circinus's middle crosses the north-south line of the sky at 9 pm local solar time. See How we know.
Sources
- IAU: The Constellations. Names, meanings, pronunciations and boundaries
- IAU Working Group on Star Names. The official names of stars
- astronomy-engine. The MIT licensed library that does the calculations, run on the page's build machine and in the app
- HYG database v4.4 (astronexus). Distances, spectral types and luminosities, licence CC BY-SA 4.0