How to find Perseus
When to look
November, December, January evenings
Face north-east, then high
A curving line of stars running from Cassiopeia's W down towards the Pleiades, with Mirfak, its brightest star, in the middle of the curve. Autumn and winter evenings: north-east after dark in October, high overhead in December and January. The drawing below is made from the real positions of its 7 stars, as the sky looks when you face it, with bigger dots for brighter stars. No telescope needed.
Perseus is a curvy line of stars between Cassiopeia's W and the Pleiades. The Perseid shooting stars in August come from here.
Perseus lies along the Milky Way between Cassiopeia and the Pleiades. Its brightest star, Mirfak, sits in a rich bunch of stars that looks wonderful in binoculars. Every August the Perseid meteors seem to shoot out of this part of the sky.
Algol, in Perseus, is a pair of stars that take turns passing in front of each other. Every 2 days and 21 hours the dimmer one blocks the brighter, and Algol fades to about a third of its usual brightness for a few hours. You can watch it happen with bare eyes, by comparing it with Mirfak.
The stars in it
Eta, Gamma, Mirfak, Delta, Epsilon, Zeta, Algol. The brightest is Mirfak.
How to find it
- Go out after dark with a grown-up, and give your eyes ten minutes away from screens.
- Face north-east, then high and look for: a curving line of stars running from Cassiopeia's W down towards the Pleiades, with Mirfak, its brightest star, in the middle of the curve.
- Hold up this page's drawing or the printed card and match the shape to the sky. If the sky is clear.
More star patterns
“Star patterns turn through the night, so the shape may be tipped on its side. Turn your head, not the sky.”