M51 - The Whirlpool Galaxy
- Type: Galaxy
- CONSTELLATION: Canes Venatici
- Distance: 31 million light-years
- Magnitude: 8.7
- APPARENT DIAMETER: 13.8’ x 11.7’
A favorite with astrophotographers, images of the Whirlpool Galaxy are simply stunning - but be warned, you’ll most likely need a larger scope to find a view to rival them. This face-on spiral galaxy lies within the same binocular field of view as Alkaid, in neighboring Ursa Major, and can be seen in 10x50 binoculars as a faint, fuzzy star.
A small telescope will show a small, hazy patch, a little elongated to the north. This elongation is caused by NGC 5195, a satellite galaxy that passed the Whirlpool several hundred million years ago. Under good skies and using averted vision, you may be able to discern the spiral arms through a medium-sized scope, but realistically, you’ll need a 250mm or larger to see the galaxy at its best.
Image source: Martin Pugh