There is so much going on in this wide field of view on the border of Cassiopeia and Cepheus that it is hard to know where to start! The largest object is The Lobster Claw Nebula (Sh2-157) in the upper right quadrant, with the small cluster, NGC 7510, above and to its left. The small bright nebula in the upper left is NGC 7538. In the middle lower portion of the image is a very small looking Bubble Nebula (NGC 7635). Finally the open cluster M52 (NGC 7654) is glistening in the lower left corner.

The northern section of the Lobster Claw Nebula has a ring shape due to the stellar wind of several giant stars. The southern section is illuminated because of excited particles caused by light radiation from stars with a spectral type O. Inside this nebula there is a very young star cluster, this is the latest generation of a process of star formation.

The open cluster NGC 7510 lies on the boundary of Cepheus and Cassiopeia. It is estimated to be 10 million years old and the light from the cluster has undergone partial extinction by interstellar gas and dust.

The nebula NGC 7538 also lies within this region of the sky. It is home to the biggest yet discovered protostar which is about 300 times the size of the Solar System. It is an active site of star formation and home to several luminous near-infrared and far-infrared sources.

The Bubble Nebula, NGC 7635, is a star surrounded by a giant molecular cloud. The Bubble is illuminated by the star’s intense ultraviolet radiation and is still growing due to the constant pressure of stellar wind.

The open cluster M52 has an apparent magnitude of 5.0 with its brightest star having a magnitude of 11. It is a compressed star cluster populated by many faint stars.

Research Assistant: Hannah Wilson