{'fraction_non_alphanumeric': 0.04622741764080765, 'fraction_numerical': 0.02709883103081828, 'mean_word_length': 4.473837209302325, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
The discovery of Jupiter’s four largest satellites 105 years before Galileo Galilei

In his painting The Three Philosophers, Giorgio da Castelfranco (aka Giorgione, 1478-1510) portrayed Aristarchus of Samos, a great mathematician and astronomer of his time, the astronomer and geographer Ptolemy of Alexandria, and Pythagoras of Samos, antiquity’s most renowned mathematician. 1 Almost as an aside, Giorgione’s painting captured a revolutionary discovery, which is shown on the document that Aristarchus holds in front of his chest: The observation of Jupiter’s four largest satellites, 105 years before Galileo Galilei’s discovery. 2 1. Aristarchus’ document In the black-and-white scan of the document one can identify the word “ J o v i s “ in the upper right-hand corner. Jovis is the Latin nominative and genitive case of Jupiter. The word “ J u v i s “, which also stands for “Jupiter” can be seen in the middle of the document. 3 The of the reference is clear now: It is Jupiter, the fifth planet of our solar system seen from the Sun. The original size of the document is 4 by 5 inches (reddish-brown paint on a yellow background, Fig. 1).The document contains an astronomical drawing. It illustrates two stages of a solar eclipse involving two celestial bodies, the Sun and the Moon. First, one can make out a small oval object to the left of the Sun. Second, the Moon has passed in front of the Sun; the result is a partial solar eclipse. Both positions of the Moon are illustrated by reference lines (Fig. 2). Giorgione may have observed this eclipse on 1 October 1502. 1 c. 1506, Kunsthistorisches Museum, Wien. 2 See for details Frank Keim, Die Entdeckung der Jupitermonde 105 Jahre vor Galileo Galilei (Frankfurt: Peter Lang, 2009). 3 S. Ferino-Pagden, G. Nepi Scirè, , eds., Giorgione: Mythos und Enigma (Wien: 2004) [hereafter Ferino-Pagden, Giorgione, 2004], p. 78.