Andromeda, Perseus, and Cassiopeia survey

Across the autumn Milky Way and beyond

This expanded panorama crosses several layers of the autumn sky at once. Dusty molecular clouds and young clusters in Taurus and Perseus sit in the Milky Way foreground. Farther north, Cassiopeia is crowded with ionized nebulae and recent star formation. Beyond all of them, the galaxies of the Andromeda subgroup and M33 appear through the same line of sight. The nested views turn one broad field into a map of radically different physical scales and distances.

• Local Group galaxies: M31, M32, M110, NGC 147, and NGC 185 belong to the Andromeda system, while M33 is another major Local Group spiral. They share the map but lie millions of light-years beyond every Milky Way nebula and cluster in the foreground.
• Cassiopeia star formation: The Heart, Soul, and Pacman nebulae trace separate ionized regions where young massive stars illuminate and erode their natal clouds.
• A stellar endpoint: SH2-188 is a planetary nebula rather than a star-forming cloud. Its strongly one-sided shell records the motion and interaction of an aging star’s ejecta with the surrounding interstellar medium.
• Perseus molecular clouds: NGC 1333 and NGC 1579 reveal reflection nebulosity, embedded stars, and active stellar birth inside dusty clouds. The California Nebula is a much larger ionized structure projected into the same broad neighborhood.
• Nearby open clusters: The Pleiades and M34 are populations of stars born together in the Milky Way, but they differ markedly in age, concentration, and their relationship to surrounding dust.