Triangulum Unveiled: A Face-On View of M33 and Its Stellar Nurseries
APOD presents Messier 33, a near face-on spiral in the Triangulum Galaxy, about 50,000 light-years across and roughly 3 million light-years from the Milky Way, likely a satellite of Andromeda. The image highlights blue star clusters and pink H II regions along its loosely wound arms, with NGC 604 standing out as a bright star-forming region; the population of well-measured variable stars in M33 helps anchor the cosmic distance scale.