IC 1805 - The Heart Nebula, is also classified in the Sharpless catalog as Sh2-190. It lies at an approximate distance of 2,500 lightyears in the constellation Cassiopeia. It is a HII region of gas and dust that is illuminated by young massive stars in an open cluster located in the center of the nebula. This cluster is designated Melotte 15 and contains a few stars with masses almost 50 times the mass of our Sun. The intense radiation and stellar winds of these stars are the major sources shaping the features, columns, and pillars of this impressive celestial vista.
The image above is known as a mapped, or false, color image and was acquired using narrowband filters. It was assembled using the standard Hubble palette with SII mapped to Red, Ha mapped to Green and OIII mapped to Blue. The stars were overlaid with bi-color data from a Ha,OIII,OIII image. The near true color (Ha/OIII/OIII) version of the image may be viewed here.
1 https://en.wikipedia.org/wiki/Heart_Nebula