A face-on spiral galaxy in Ursa Major, about 21 million light-years away and notable for its asymmetric structure — one spiral arm is significantly more extended than the others, likely the result of a past gravitational interaction with a companion galaxy. M101 is enormous, spanning roughly 170,000 light-years in diameter, making it nearly twice the size of the Milky Way.

The galaxy's face-on orientation gives a textbook view of spiral arm structure, dust lanes, and star-forming regions. Several of its HII regions are so large and bright they have their own NGC catalogue entries. M101 hosted a bright supernova (SN 2023ixf) in May 2023 (seen here), a reminder that even familiar objects can surprise us.