M13 - Hercules Cluster
M13 is the brightest and most famous globular cluster in the northern sky, visible to the naked eye under dark conditions. It contains several hundred thousand stars.
Distance: 22,200 light-years
Apparent Magnitude: 5.80
Apparent Size: 20'
Constellation: Hercules
Object Type: Globular Cluster (Class V)
Key Features:
- Best northern globular cluster
- ~300,000 stars
- Age: 11.65 billion years
- 145 light-years diameter
- Arecibo message sent here in 1974
- Visible naked eye
Best Imaging Season: April - September
Optimal Integration: 3+ hours
