Astrophoto of the month - March 2022 - The Heart Nebula, IC1805

The Heart Nebula

The Heart Nebula is a so-called HII region approximately 7500 light-years away, a huge interstellar gas cloud composed mainly of hydrogen, in which young stars are born. The gas cloud is shaped by the stellar wind and ultraviolet radiation from massive hot stars in the nebula's star cluster, the Melotte 15, as this ultraviolet radiation induces light emission in interstellar clouds.

The color of the Heart Nebula

The Heart Nebula, as all similar gas nebulae in the Milky Way, would appear red to the naked eye if it were bright enough. However, by using filters similar to those introduced by the Hubble Space Telescope (Sulfur-II, Oxygen-III, and Hydrogen Alpha) much more contrasted structures and previously unseen details can be captured with long exposure shots. As a result, the color of the nebula appears not in red, but in an orange and blue, but with much more details and differences in contrast.

How it was made?

Péter Feltóti's image is of outstanding detail and depicts a larger part of the nebula than usual. The image was taken with a 20 cm Newtonian telescope, an astronomical CCD camera and Sulfur-II, Oxygen-III, hydrogen-alpha filters, and shows a bluish color for ionized oxygen gas and a yellowish-brown color for hydrogen and sulfur gasses.