Editing Nebulium (section)

{{Short description|Proposed element found in astronomical observation of a nebula}}
[[File:NGC6543.jpg|thumb|right|Cat's Eye Nebula (NGC 6543)]]
[[File:NGC 6543 "Cat's Eye".png|thumb|Cat's Eye Nebula (NGC 6543)]]
'''Nebulium''' was a proposed [[chemical element|element]] found in [[astronomical observation]] of a [[nebula]] by [[William Huggins]] in 1864. The strong green [[emission spectrum|emission]] lines of the [[Cat's Eye Nebula]], discovered using [[spectroscopy]], led to the postulation that an as yet unknown element was responsible for this emission. In 1927, [[Ira Sprague Bowen]] showed that the lines are emitted by [[doubly ionized oxygen]] (new style [[oxygen|O]]{{sup|2+}}; old style O{{sup|III}}), and no new element was necessary to explain them.