Constellation, UMi
Ursa Minor: the Little Bear
Ursa Minor covers 256 square degrees of sky, the 56th largest of the 88. Its brightest star is Polaris. It is best placed in the evening sky in June.
Show Ursa Minor in the live sky
Ursa Minor at a glance
| Fact | Value |
|---|---|
| IAU abbreviation | UMi |
| Meaning | the Little Bear |
| Pronounced | ER-suh MY-ner |
| Genitive, used in star names | Ursae Minoris (for example a Bayer name such as α Ursae Minoris) |
| Area | 256 square degrees, number 56 of 88 by size |
| Stars to magnitude 6 in our catalogue | 25 |
| Brightest star | Polaris, magnitude 2.0 |
| Best seen | Evenings in June, when it is highest at 9 pm |
| Declination range | 66° to 90° |
| Borders | Draco, Camelopardalis, Cepheus |
Where on Earth you can see Ursa Minor
Ursa Minor spans declinations 66° to 90°. Every part of it rises above the horizon at some moment for observers between latitudes 0°S and 90°N. Some of it can be seen from latitudes 24°S to 90°N. North of 24°N 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 | 32° |
| New York | 40.7°N | Never sets | 55° |
| London | 51.5°N | Never sets | 65° |
| Tromsø | 69.6°N | Never sets | 84° |
| Tokyo | 35.7°N | Never sets | 50° |
| Sydney | 33.9°S | Never rises | below the horizon |
Ursa Minor's named stars
These stars in Ursa Minor have names approved by the IAU Working Group on Star Names. Magnitude is brightness: a lower number is brighter, and the faintest stars seen with the naked eye on a dark night are about magnitude 6.
| Star | Designation | Magnitude | Distance (light-years) |
|---|---|---|---|
| Polaris | α Ursae Minoris | 1.97 | 430 |
| Kochab | β Ursae Minoris | 2.07 | 130 |
| Pherkad | γ Ursae Minoris | 3.00 | 490 |
| Yildun | δ Ursae Minoris | 4.35 | 170 |
Distances are about, from the HYG database (Hipparcos parallax), and "not known" means the catalogue has no reliable parallax for that star.
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 Ursa Minor'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