| Helium was first discovered by two astronomers, the French scientist Pierre Janssen and the English astronomer Norman Lockyer who observed a bright yellow line in the in spectrum of the Sun during the solar eclipse of 1868 (which was named the D3 line). In 1871 Lockyer explained it by the presence of a new element in the Sun. On 26 March 1895 British chemist William Ramsay isolated helium on Earth the gas liberated from the mineral cleveite, in the spectrum of which he noticed a bright-yellow line that matched the D3 line observed in the spectrum of the Sun. |
| The abundance of helium on the Earth are estimated as 5x1014m3. In the Earth& |