A nebula is a giant cloud of dust and gas in space. Made mostly of hydrogen and helium, the nebulae (more than one nebula) are the space between the stars. Interestingly, this space is also known ...

Charles Messier also produced a catalog of over 100 prominent nebulae in 1781. Messier was interested in comets, so his list was a set of fuzzy objects that might be mistaken for comets.