Hercules is a large northern constellation of the summer sky, a kneeling hero drawn upside down, with the Keystone at its centre and the great globular cluster M13.
At a glance
| stars in the figure | 21 |
|---|---|
| nearest star of the figure | Mu Herculis, 27.1 light-years (8.31 pc) |
| farthest star of the figure | Theta Herculis, 753 light-years (231 pc) |
| depth | the farthest is 28 × farther than the nearest |
Read off the piece’s own catalogue, the same values it draws with.
About Hercules
Hercules is the Greek hero Heracles, drawn kneeling and upside down, his head near Rasalgethi and his foot near the dragon’s head. At the centre is the Keystone, four stars in a lopsided square. Rasalgethi is a red giant that varies in brightness and has a companion. Kornephoros is the brightest star of the figure.
On one side of the Keystone lies M13, the finest globular cluster of the northern sky, a ball of old stars just visible to the naked eye under dark skies; M92 is another, slightly smaller cluster nearby. The Sun’s own motion among its neighbours points roughly towards Hercules. The figure is best seen on northern summer evenings.
What you see in the piece
Flown out to, the hero falls apart: Mu Herculis is a near neighbour while Theta Herculis lies far behind, and M13, far beyond them all, stays together as a real cluster.
Questions
Where is M13 in Hercules?
M13 lies on the western side of the Keystone, on the line between Eta and Zeta Herculis, closer to Eta, and shows as a faint fuzzy star in binoculars.
How far away are the stars of Hercules?
They range from Mu Herculis, 27.1 light-years (8.31 pc), to Theta Herculis, 753 light-years (231 pc): the farthest is 28 × farther than the nearest.