Galileo Galilei

Istoria e dimostrazioni intorno alle macchie solari, in Roma, appresso Giacomo Mascardi, 1613

[BNCF: Palat. (11).C.10.5.28]

The cause of sunspots was controversial. In three letters to Marcus Welser (1558-1614), printed as Description and Demonstrations concerning Sunspots, Galileo discarded the hypothesis of the Jesuit father Christoph Scheiner (1573-1650). Sunspots were not due to swarms of corpuscles moving between the Earth and the Sun, but they were located at the surface of the Sun.

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