nebulium

American  

[nuh-byoo-lee-uhm] / nəˈbju li əm /

noun

Astronomy.

1. a hypothetical element once thought to be present in emission nebulae because of certain unidentified spectral lines, now known to be forbidden transitions of oxygen and nitrogen ions.

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Etymology

Origin of nebulium

First recorded in 1895–1900; nebul(a) + -ium

Example Sentences

Certain unfamiliar lines in the spectra of far off nebulae have long been thought by astronomers to be made by a mysterious element which they called nebulium.

From Time Magazine Archive

Accordingly they created by mutual consent a new element, called it "nebulium," and doubted that it existed.

From Time Magazine Archive

When this nebula is observed with a slitless spectrograph the hydrogen and nebulium components are seen as circular discs, but the hydrogen discs are larger than the nebulium discs.

From Popular Science Monthly Oct, Nov, Dec, 1915 — Volume 86 by Anonymous

The whole thing aglow with the green light of nebulium and blazing with the stars behind it.

From Out Around Rigel by Wilson, Robert H.

The nebulium lines are relatively strong in the central denser parts of the Orion and Trifid nebulae, but the hydrogen bright-lines are relatively very strong in the faint outlying parts of these nebulae.

From Popular Science Monthly Oct, Nov, Dec, 1915 — Volume 86 by Anonymous