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Jupiter and its satellites

(c) Istituto e Museo di Storia della Scienza di Firenze Galileo discovered the "Moons" of Jupiter between January and February 1610.

One of the arguments against the Copernicus heliocentric model was the oddity of the Earth-Moon system: if all planets have to orbit around the Sun, why does the Moon orbit around the Earth? The Galileo discovery showed that other moon systems do exist and it paved the way to a universal theory of gravity.

See below how Jupiter would have been seen from Veneto, January 13, 1610 ...through a telescope with an infinite aperture diameter, a 370X magnification factor, and under inconceivably stable atmospheric conditions!

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In the video below, Jupiter sustain both the effect of diffraction and atmospheric turbulence.

Flash Video - 656.5 kb

Pay attention to the position of satellites, and see how they seem to “move” slightly differently one from each other and from Jupiter itself: they are observed in sufficiently far-off directions so that their light crosses distinct portions of turbulent atmosphere layers.

Jupiter seen by Galileo ©Chiara Marmo - Photothèque Planétaire d’Orsay is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

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