Object Analysis

The Heart Nebula (IC 1805) is an emission nebula roughly 7,500 light-years away in the constellation Cassiopeia. It displays glowing ionized hydrogen gas and darker dust lanes. The nebula is formed by plasma of ionized hydrogen and free electrons.

The very brightest part of this nebula (the knot at the center) is separately classified as NGC 896, because it was the first part of the nebula to be discovered. The intense red output of the nebula and its morphology are driven by the radiation emanating from a small group of stars near the nebula's center, known as Melotte 15.

Melotte 15 contains a few bright stars nearly 50 times the mass of our Sun, and many more dim stars that are only a fraction of our Sun's mass. The stellar winds from these massive stars have blown a giant bubble in the surrounding gas, sculpting the "heart" shape.