Nebulium was the name given to the unknown element observed by English astronomer, William Huggins. Huggins was investigating the spectra of various stellar bodies when he discovered a vivid green line in the spectra of a planetary nebula. After looking closer, he discovered the line was actually two lines close together. This part of the spectra did not associate with any known element at the time. He concluded planetary nebulae were large masses of gas that did not form a star. He also named his unknown element nebulium.
Bowen showed these lines could be produced by oxygennitrogen ions at high temperatures and not some undiscovered element. Find out what else occurred on this day in science history.