In this detailed image of the Hubble Space Telescope M31 PHAT mosaic image, several object types are labeled, including dust lanes, stellar clusters, Milky Way stars, and star-forming regions. This image is a small section of the full mosaic that includes near-ultraviolet, visible, and near-infrared observations obtained with the Wide Field Camera 3

Illustration: NASA, ESA, and Z. Levay (STScI/AURA);
Science: NASA, ESA, J. Dalcanton, B.F. Williams, and L.C. Johnson (University of Washington), and the PHAT team