Crescent Nebula in HOO
This nebula was discovered by a fellow named William Herschel, a British astronomer and composer. He did a lot of research on double stars and is most famously known for discovering the planet Uranus which at the time was the first planet discovered in a thousand years.
William Herschel was a self taught Astronomer, who built his own telescopes. He and his sister would make these mirrors by painstakingly polishing a piece of metal until it was extremely reflective, the largest of which is the Great Forty-Foot telescope with a focal length of about 12000mm.
Courtesy: Ast Robin