Pierre Janssen (1824–1907)

Born 1824 CE, died 1907 CE.

Pierre Jules César Janssen (22 February 1824 – 23 December 1907), usually known as Jules Janssen, was a French astronomer who, along with English scientist Joseph Norman Lockyer, is credited with discovering the gaseous nature of the solar chromosphere, and with some justification the element helium.

Text from the Wikipedia article Pierre_Janssen, licensed CC BY-SA 4.0.

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Pierre Janssen (1824–1907)

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