How to find the North Star
Face north and find the Big Dipper. The two stars at the end of its bowl point to Polaris, the North Star, about 5.3 times their own gap away. Polaris sits only 0.62° from the north celestial pole, so it hardly moves while the sky turns around it, and its height above the horizon is your latitude. Below: where the Big Dipper is at 10 p.m. each month, how high Polaris stands from 25° to 50° north, and a calculator for any place and hour.
Where is the North Star tonight?
Enter your latitude and longitude (west is negative), the time zone your clock is on, a date and an hour. The calculator says where the Big Dipper is around Polaris, how high its stars are, and where Cassiopeia is, facing north.
the Big Dipper, around Polaris, facing north
The date starts at today; without JavaScript, the example above is New York at 10 p.m. on January 15, 2027. Left and right are as you stand facing north: right is east.
Find it from the Big Dipper
The Big Dipper is seven bright stars shaped like a ladle. The two at the far end of the bowl, away from the handle, are Merak and Dubhe, the pointers. Draw a line from Merak through Dubhe and keep going about 5.3 times the gap between them. There is Polaris, about as bright as the pointers themselves.
Polaris is not a very bright star: about magnitude 2.0, between Dubhe (1.8) and Merak (2.4). It is α Ursae Minoris, a star of the Little Dipper, not of the Big one.
The Big Dipper at 10 p.m., month by month
The whole sky turns once a day around Polaris, counterclockwise as you face north, and the same hour drifts a little each night, so the Dipper's place at 10 p.m. moves through the year. In spring evenings it stands above Polaris in May; in autumn it lies low, lower left in October.
| Month | Around Polaris | Height |
|---|---|---|
| January | right, handle down | 13°–39° |
| February | right, handle down | 28°–54° |
| March | upper right, handle right | 36°–61° |
| April | upper right, handle right | 55°–73° |
| May | above Polaris, handle right | 65°–75° |
| June | upper left, handle up | 52°–78° |
| July | upper left, handle up | 36°–59° |
| August | left, handle up | 21°–40° |
| September | lower left, handle left | 11°–23° |
| October | lower left, handle left | 5°–12° |
| November | below Polaris, handle left | up to 16°, 1 of 7 below the horizon |
| December | lower right, handle down | 3°–25° |
At 40° north the sky is dark by 10 p.m. by the clock in every month. From March to early November the clock is on daylight saving time, so 10 p.m. by the clock is 9 p.m. standard time; the table follows the clock.
Find it from Cassiopeia
When the Big Dipper is low, Cassiopeia is high: the W of five stars sits on the other side of Polaris. Extend the two outer sides of the W until they meet. Draw a line from that point through the middle star of the W (γ Cassiopeiae) and go about 5.0 times that distance further. The line passes within 0.8° of Polaris.
How high is the North Star?
Polaris stands about as high above the northern horizon as your latitude: roughly 41° in New York, 34° in Los Angeles, 42° in Chicago. It is 0.62° from the pole, so over a night it rises and falls by that much: in New York, between 40.1° and 41.3°. The Big Dipper circles it at a much larger distance. At 40° north, Alkaid, the last star of the handle, just dips below the horizon at the Dipper's lowest; in New York, at 40.7°, it stays up all night. At 25° north the whole Dipper sets.
| Latitude | Polaris altitude | Dipper stars that set |
|---|---|---|
| 25° | 24.4°–25.7° | all 7 |
| 30° | 29.4°–30.6° | 6 of 7 |
| 35° | 34.4°–35.6° | 2 of 7 |
| 40° | 39.4°–40.6° | 1 of 7 |
| 45° | 44.4°–45.6° | none |
| 50° | 49.4°–50.6° | none |
What about a compass?
A compass points to magnetic north, not to Polaris. NOAA describes the difference, the magnetic declination, as the angle between magnetic north and true north, and it changes with place and over time. Its calculator gives the value for where you are. Polaris itself marks true north to within about a degree.
Where Angel Step fits
Angel Step reads only your step count from Apple Health and shows it as one number on a living sky. It does not chart the stars; that is this page's job. A clear night and a short walk away from the streetlights are all it takes to find Polaris yourself.
Sources
- IPAC, Caltech — Cool Cosmos, How can I find the North Star?: the pointer stars of the Big Dipper; the North Star is not a very bright star. IPAC
- IAU Working Group on Star Names — the official star names used here (Polaris, Dubhe, Merak, Alkaid and others). IAU WGSN
- NOAA National Centers for Environmental Information — magnetic declination. NOAA
- ESA Hipparcos, new reduction (VizieR I/311) — the star positions behind the calculator. VizieR
Updated