An Etymological Dictionary of Astronomy and Astrophysics

Chemical element; symbol He; atomic number 2; atomic weight 4.0026; melting point below -272°C at 26 atmospheres pressure; boiling point -268.934°C at 1 atmosphere pressure.

See also: Helium, from Gk. helios “sun;” cognate with
Persian hur “sun”, variant xor;
Mid.Pers. xvar “sun;” Av. hû-, hvar- “sun;” Skt.
surya-; L. sol; O.H.G. sunna; Ger. Sonne; E. sun;
PIE *sawel- “sun.”
The element was discovered by spectroscopy during a solar eclipse in the Sun’s chromosphere in 1868 by the French astronomer Pierre-Jules-Cesar Janssen (1824-1907).