Hercules
The constellation of Hercules covers a very large area of the sky though its main stars are not very bright. Four stars in the middle of the constellation form an asterism known as the Keystone. In the middle of one of its sides, between h and x is a globular star cluster - M13. It is barely visible as a faint patch of light to the naked eye, and using a 6" telescope you should be able to resolve the outer stars. The cluster contains about 100,000 stars and is 22,000 light years away. M92 is also a Globular cluster and is a little further away at 35,000 light years but its outer stars can also be resolved with a 6" telescope.
There are several easy double stars in Hercules that are worth searching out with z being an interesting pair as their period is 34.5 years so the position and separation change quickly - one to keep an eye on.
| Telescopic Objects | Main Stars | ||||||
| Object | Magnitude | Comments | Name | Magnitude | Distance L/Y | Comments | |
| M13 | 5.9 | Globular Cluster | b Kornephoros | 2.7 | 101 | ||
| M92 | 6.5 | Globular Cluster | z Rutilicus | 2.8 | 31 | ||
| a Rasalgethi | 3 to 4 | 218 | Variable star | ||||
| d Sarin | 3.1 | 91 | |||||
| p | 3.1 | 391 | |||||
| Variable Stars | Range | Period | Multiple Stars | ||||
| a Rasalgethi | 3 - 4 | 100 Days | Name | Magnitude / Separation" | |||
| a Rasalgethi | 3 - 4 & 5.4 / 4.7" | A semi variable binary system | |||||
| l | 5.3 & 6.5 / 28.4" | ||||||
| g | 3.8 & 9.8 / 41.6" | ||||||
| d | 3.7 & 8.2 / 8.9" | An optical pair | |||||
| z | 2.9 & 5.5 / 1.6" | Period of 34.5 years | |||||
Check out the other Constellations with the navigation menu below