APOD 10: Anemic Spiral NGC 4921 from Hubble

2013 November 25

Presently estimated at 310 million years light years away. Hubble Space Telescope was used to identify Cepheid variable stars as stellar markers of distance. It is a member of the Coma Cluster of Galaxies, and has been informally dubbed as anemic due to its low rate of star formation and low surface brightness. Within this span of the Anemic Spiral is a bright nucleus, a prominent ring of star dust, blue clusters of new stars, smaller companion galaxies, a bright center bar, and unrelated stars in the Milky Way.