Pierre Janssen and Joseph Norman Lockyer, French and English astronomers, 1868. Pierre Jules Cesar Janssen (1824-1907), left, and Joseph Norman Lockyer (1836-1920). In 1868 while making spectroscopic studies of solar prominences, working independently, both men observed a yellow line in the solar spectrum. Lockyer named it Helium from helios (sun). Obverse of a commemorative medal. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Heritage Images / Oxford Science Archive |
Bildgröße: | 4204 px × 4154 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
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