Hercules
Her · genitive Herculis · northern sky
At a glance
- Catalogued stars
- 242
- Visible to the eye
- 242 stars
- Brightest star
- Kornephoros (2.78)
- Best seen
- June
- Declination span
- +14.4° to +46.3°
- Nearest star
- 86Mu Her · 27.1 ly
Visible from everywhere north of about 44°S.
When and where to look for Hercules
Hercules crosses the meridian — its highest point in the sky — at local midnight around June, which makes the months from May to July the easiest time to find it in the evening. It spans declinations +14.4° to +46.3°, so visible from everywhere north of about 44°S.
The quickest way to find it is to open the live AR sky map and point your phone at the sky — if Hercules is above your horizon right now, its figure is drawn in the position it genuinely occupies above you.
Brightest stars in Hercules
| Star | Mag | Type | Distance |
|---|---|---|---|
| Kornephoros27Bet Her | 2.78 | G8III | 139.1 ly |
| Rasalgethi64Alp1Her | 2.78 | M5IIvar | 359.6 ly |
| 40Zet Her | 2.81 | F9IV | 35 ly |
| Sarin65Del Her | 3.12 | A3IVv SB | 75.1 ly |
| 67Pi Her | 3.16 | K3IIvar | 376.6 ly |
| 86Mu Her | 3.42 | G5IV | 27.1 ly |
Magnitude runs backwards: lower numbers are brighter, and anything below about 6.5 is beyond the naked eye under a dark sky.
What Hercules is made of
The catalogue lists 242 stars within Hercules, of which 242 are magnitude 6.5 or brighter — the limit of what an unaided eye picks up under a genuinely dark sky. The rest need binoculars or a telescope.
Spectral make-up
Spectral class is a temperature ordering, running from O at around 30,000 K down to M below 3,500 K. A constellation is a direction, not a group, so this is simply what happens to lie along that line of sight.
The closest catalogued star in this direction is 86Mu Her at 27.1 light years. The most distant is HD 153834 at roughly 3,106 light years — stars that appear side by side here are nothing of the sort.
Deep-sky objects in Hercules
- Hercules Cluster — globular cluster
These are marked on the sky map, so you can see where they sit relative to the constellation figure in real time.