Sharpless 2-157 (sometimes called Sh 1-109), also known as the Lobster Claw Nebula, is an emission nebula located about 8 000 to11,000 light-years away in the constellation of Cassiopeia, lying along the Perseus Arm of the Milky Way. The H II complex is dominated by layered ionization fronts and wind-sculpted cavities that outline the “claw,” with the compact ring Sh2-157A, near the star WR 157, embedded on its southern rim. Several young clusters—most notably Markarian 50—and massive OB stars provide the ionizing radiation that shapes the nebula’s scalloped edges.
IC 1470 is a compact H-II region located in the Perseus arm of the Milky Way. Inside is the small star cluster [BDS2003] 39. The nebula is excited to shine by an O8 V star. Its age is estimated to be one to three million years. Its measured distances from us range from 8 740 to 17 300 light years.
Further east of IC 1470 one comes across three other small star clusters: NGC 7510 at a distance from Earth of 11 400 light-years and an estimated age of 38 million years. King 19 is located at a distance of 1 967 parsecs and has an estimated age of 360 million years. Kronberger 23 is home to the variable star QT Cephei.
The famous Bubble Nebula (NGC 7635) is located northeast of Sh 2-157.
