Lockyer, Sir (Joseph) Norman

(1836–1920) British astronomer: discovered helium in the Sun.

As a young civil servant at the War Office, Lockyer developed an interest in astronomy and made it his career. He was particularly interested in the Sun and in the use of the recently-introduced methods of spectral analysis. Following the eclipse of 1868 Lockyer discovered, independently of the French astronomer P Janssen (1824–1907), that solar prominences could be seen with a spectroscope at any time, not merely during eclipses, and that the forms of the prominences slowly changed with time. He identified an unknown element in the Sun’s spectrum, which he named helium and which was subsequently isolated in the laboratory by in 1895. In 1873 he proposed that some unfamiliar solar spectral lines were caused by the dissociation of atoms into simpler substances with their own spectra (the electron was not to be discovered until 20 years later; we now recognize the dissociation as loss of electrons). Lockyer was also interested in archaeology, pioneering the study of possible astronomical alignments with ancient structures. He founded the Science Museum in London and also the science journal Nature , of which he was editor for 50 years.

He was a fearless fellow, in debate and as an expedition leader in pursuit of solar eclipses, and he was a founder of solar astrophysics.