Pierre Jules César Janssen

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Janssen, Pierre Jules César


Born Feb. 22, 1824, in Paris; died Dec. 23, 1907, in Meudon. French astronomer. Member of the Paris Academy of Sciences (1873) and of the Royal Society of London (1875). One of the founders of the spectral analysis of celestial bodies.

In 1868 and independently of J. N. Lockyer, Janssen invented the spectral method of observing solar prominences on the limb of the sun’s disk during periods when the sun was not in eclpse.


Neuimin, G. N. “P. Zh. Zhansen.” Izvestiia Russkogo astronomicheskogo obshchestva, 1909, issue 14, no. 8, pp. 285–90.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.