The very large emission nebula NGC2237, also known as Rosette Nebula, is part of an even much larger area of nebulosity in the constellation Monoceros.

The emission nebula NGC281 in the constellation Cassiopeia, named after the well known videogame character Pacman with which the resemblance is striking.

The emission nebula NGC6888, also known as Crescent nebula, looks like a big brain-like structure surrounded by a lot of H-alpha emitting nebulosity.

Perhaps the most photographed nebula in the night sky, M42, better known as the Orion Nebula in the constellation Orion. And… my first astro image.