IC 5146 Emission and Reflection Nebula in Cygnus.
The Bubble Nebula is an ionized hydrogen emission nebula 7,800 light years away, created by stellar winds from the Wolf-Rayet O-type star SAO 20575.
Melotte 15 is a very young star cluster in the IC 1805 nebula, also known as the Heart Nebula. It consists of massive OB stars with a mean age of only 1.5 million years. Melotte 15 is one of the core clusters of the Cas OB6 stellar association.