Don’t let this galaxy deceive you…it’s not as small as it looks from Earth! Messier 101, or M101, is over 170,000 light years across, and contains over a trillion stars. For comparison, our galaxy, the Milky Way, is ‘only’ 100,000 light years across. The Pinwheel Galaxy makes for a great image, as well as study, thanks to its face-on orientation. It’s spiral arms are easy to see, with dark dust lanes running through the core.

The stars closer to the core are generally older, and show up as yellow. No, stars don’t really “yellow” as they age. It’s more that the stars that live longer give off more yellow light than the shorter-lived massive blue stars. Those blue stars are more prevalent in the outer arms of the galaxy, as these are the regions where new stars are formed. You can actually see some of those purple-ish star-forming nebulae in this photo.

I used an unmodified camera (Sony A7II) to create this image, so the nebulae really “lack.” However, they’re there!