Perseus, the Hero, is a northern constellation of the autumn and winter sky, holding the eclipsing star Algol, the Double Cluster and the radiant of the Perseids.
At a glance
| stars in the figure | 19 |
|---|---|
| nearest star of the figure | Iota Persei, 34.4 light-years (10.5 pc) |
| farthest star of the figure | Menkib, 1,240 light-years (382 pc) |
| depth | the farthest is 36 × farther than the nearest |
Read off the piece’s own catalogue, the same values it draws with.
About Perseus
Perseus is the hero of Greek myth who beheaded Medusa and rescued Andromeda; he is drawn holding the Gorgon’s head, marked by Algol, the demon star. Algol is an eclipsing pair: every few days the fainter star passes in front of the brighter one and Algol visibly dims for some hours. Mirfak, the brightest star, sits in the Alpha Persei Cluster, a loose group of young blue stars.
Perseus lies along the Milky Way. On its border with Cassiopeia is the Double Cluster, two star clusters side by side. Menkib, a hot blue star, lights the California Nebula. The Perseid meteors, the most watched shower of the northern summer, seem to radiate from the figure. Perseus is best seen on northern autumn and winter evenings.
What you see in the piece
Flown out to, the hero scatters: Iota Persei is a near neighbour, while Menkib lies far behind, beside the gas it lights, and the stars of the Alpha Persei Cluster stay together as a real group.
Questions
Why does Algol change in brightness?
Algol is an eclipsing binary. Its two stars orbit each other edge-on to us, and when the fainter one passes in front of the brighter, the light drops.
How far away are the stars of Perseus?
They range from Iota Persei, 34.4 light-years (10.5 pc), to Menkib, 1,240 light-years (382 pc): the farthest is 36 × farther than the nearest.