studies of the surface



Jules Janssen (Feb. 24, 1824 to Dec. 23, 1907): French astronomer who, among other things, was known for his 1904 Atlas de photographies solaires: photographic studies of the surface of the sun.

1. Région Centrale (Taches et Granulations), June 22, 1885, 7h 48m 40s
2. Région Centrale (Taches et Granulations), April 1, 1894, 9h 51m 17s


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