Polaris (α UMi)
Polaris (α UMi) is a double star in the constellation Ursa Minor, magnitude 2.0.
The North Star has a faint companion visible in small telescopes. Its components (magnitudes 2.0 and 9.1; spectral types F7 Ib (yellow-white) and F3 V (yellow-white)) lie 18.4″ apart at PA 236° (measured 2016).
When and where to see it
It is best placed in the evening sky around December, when it crosses the meridian at about 10 pm local time (around midnight in November). It can be seen from everywhere north of 1°S and never sets north of 1°N.
At its highest it stands 51° up from 50°N, 36° up from 35°N, 1° up from the equator, below the horizon from 35°S.
Facts
- Type
- Double star
- Constellation
- Ursa Minor
- Designations
- α UMi, Alpha Ursae Minoris, 1 UMi, 1 Ursae Minoris, STF 93, HIP 11767
- Magnitude
- 2.0
- Position
- RA 2h 31.8m, Dec +89° 16′ (J2000)
Open AstroPilot to see when Polaris (α UMi) is highest tonight from your location, how easy it is with your telescope or binoculars, and an eyepiece view.