M101 - Pinwheel Galaxy
M101 is a face-on grand design spiral galaxy, one of the most photogenic galaxies in the night sky. Its asymmetric spiral arms show signs of tidal interaction with satellite galaxies.
Distance: 20.9 million light-years
Apparent Magnitude: 7.86
Apparent Size: 29' × 27' (nearly Moon-sized)
Constellation: Ursa Major
Morphology: SAB(rs)cd (grand design spiral)
Key Features:
- Spectacular face-on spiral structure
- 7 known satellite galaxies
- Asymmetric arms from tidal interactions
- Giant HII regions (NGC 5461, 5462)
- Large angular size - excellent for moderate telescopes
Best Imaging Season: January - May
Optimal Integration: 15+ hours for full extent
