Discovery of Helium

Helium is the second most abundant element in the Universe, but it is rare on the Earth. In fact, helium was discovered in the spectrum of the Sun before it was found on Earth (the name helium derives from helios, which is the Greek name for the Sun).

It was postulated that a set of spectral lines observed in the Solar emission spectrum that could not be associated with any known element belonged to a new element. Only then was helium discovered on the Earth and this hypothesis confirmed. On Earth, helium occurs only in certain very deep gas wells.