Science & history · Constellation guide
Ursa Minor, the Little Bear
Ursa Minor, the Little Bear, holds Polaris at the tip of its tail. Its seven main stars make a smaller, fainter ladle, the Little Dipper, that turns around the pole all night.
How to spot it: Polaris is the end of the Little Dipper's handle. Source (opens in a new tab)
The Little Dipper
Ptolemy counted seven stars in the Little Bear (opens in a new tab), in a ladle shape like the Big Dipper's, and Polaris is the end of its handle. Apart from Polaris and the two stars at the far end of the bowl, Kochab and Pherkad, its stars are fourth magnitude or fainter in the Bright Star Catalogue, so city lights easily hide the shape.
The sailors' bear
The Greeks credited Thales of Miletus with introducing the Little Bear (opens in a new tab), and said that the Phoenicians steered by it, while Greek sailors used the Great Bear. Aratus pointed out that the smaller bear is the better guide because it lies closer to the pole.
Cynosure
Aratus called the constellation Kynosoura, the dog's tail (opens in a new tab). That is the root of the English word cynosure, a guiding star or centre of attention.
Where on Earth, and when
The whole key pattern rises from anywhere north of about 1°S.
South of about 18°S, none of it rises.
North of about 18°N, the whole key pattern never sets.
Its middle climbs at least 20° high, the finder's threshold for a suggestion, from anywhere north of about 9°N.
It is highest in the evening sky, at about 9 p.m. local time, in mid-June, from either hemisphere, wherever it rises. With daylight saving time, that is nearer 10 p.m. on the clock.
Worked out by this site from the Bright Star Catalogue, for a flat, clear horizon. Hills, buildings, haze and city light all cut into this; the air also lifts objects near the horizon by about half a degree. For your own place and night, use the sky finder.
Sources
- History Ian Ridpath, Star Tales: Ursa Minor (opens in a new tab) for the figure, Thales, the Phoenicians and cynosure
- Astronomy Bright Star Catalogue, 5th Revised Ed. (Hoffleit & Warren 1991), as computed by this site's star engine (opens in a new tab) for the magnitudes of its stars