uraniaproject:

The Iris Nebula

by Albert Barr from Fort Lauderdale, Florida

Imagine a cloud of countless particles, each measuring less than a millionth of a millimeter wide. Together, however, these particles function as a special type of cosmic mirror we know as the Iris Nebula (NGC 7023). Sir William Herschel discovered the Iris Nebula in 1794. He described it as, “A star of 7th magnitude. Very much affected with nebulosity, which more than fills the field. It seems to extend to at least a degree all around; stars, such as 9th or 10th magnitude, of which there are many, are perfectly free from this appearance.” NGC 7023 received its common name, the Iris Nebula, from California astroimager Daphne Hallas. She saw a film that showed the nebula’s center and commented that it resembled an unfolding iris.