Ursa Minor

What is Ursa Minor?

Constellations· All year (N) · Polaris at the handle tip. The Little Dipper, with Polaris at the tip of its handle. The north celestial pole lies inside it, so the whole sky seems to wheel around this small constellation. Run the clock in the Sky view to watch the stars circle Polaris.

📍 Visible from where you are right now — computed in your browser

bearing · altitude · rise time · best time tonight

Ursa Minor
Image: NowSky rendering (an illustration, not a photograph)· Wikipedia
Ursa Minor star lines
Star lines — the stars used and how they connect (NowSky)

Where Ursa Minor is in your sky right now: https://nowsky.org/solar/sky?sel=con:Ursa Minor — location and time set automatically, no login.

Stars of the figure

StarMagnitude
Polaris2.0
Kochab2.1

The 2 brightest of the 9 stars used in the figure (9 lines). Lower magnitude means brighter.

Constellation basics

Seasoncircumpolar — visible all year from mid-northern latitudes
Brightest starPolaris (2.0)
How to findextend the Big Dipper's pointer stars ×5
Area rank56th of 88

Figures are representative approximations. Source: compiled from NASA and IAU public data.

Frequently asked

When can I see Ursa Minor?
circumpolar — visible all year from mid-northern latitudes.
How do I find Ursa Minor?
extend the Big Dipper's pointer stars ×5.
What is the brightest star in Ursa Minor?
Polaris, magnitude 2.
Where is Ursa Minor in the sky right now?
Open the sky view for your location and time and it shows the position in the sky right now.

Polaris pulses — a star that breathes every four days

Polaris is a Cepheid variable, a star that swells and shrinks with a period of about four days and changes slightly in brightness, and it is the nearest Cepheid in the sky. Its amplitude was 0.1 magnitude in the early twentieth century, shrank to 0.02 in the 1990s as if the pulsation were dying out, and then grew again a little. Why it behaves this way has not been explained.

Polaris also seems to have grown brighter than old records show. Ptolemy listed it as 3rd magnitude, and today it is 2nd; one reading is that the star is passing through a stage of its evolution, another that the old records are simply imprecise. The star that stands still all night and became the emblem of constancy is, in fact, changing its size and brightness at this very moment.

The constellation in depth

In Greek myth Ursa Minor is either the nymph who nursed the infant Zeus or Arcas, son of the great bear Callisto, placed beside his mother in the sky. Phoenician sailors were steering by it centuries before Christ, which is why it was long known as the "Phoenician star". Small as it is, no constellation mattered more to navigators.

Polaris, at the tip of the handle, sits about 0.7 degrees from the north celestial pole and barely moves all night. Kochab and Pherkad at the bowl are the "Guardians of the Pole"; around 1500 BC Kochab itself served as the pole star. Earth's axis wobbles on a 26,000-year cycle, so each age gets a different North Star.

Extend the line through the Big Dipper's pointer stars, Dubhe and Merak, five times and you land on Polaris. Under city lights only Polaris and Kochab show, but a dark site reveals the whole Little Dipper. Change the observer location in the Sky view and you will see that your latitude equals the altitude of Polaris. Even from a bright city it is worth learning, because it is the one fixed point in a sky that turns all night.

Related

Figures are representative approximations. Simulated positions use J2000 mean elements.