tfpsly a écrit:WhyHey a écrit:Small Solar System Bodies: All other objects orbiting the Sun.
question: la Lune ou Io sont des SSSB ??
A ton avis ?
si je pose la question c'est que je suis DANS le doute
pas tapper
on continue, dixit:
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New proposal for Resolution 5: Definition of a Planet
(1) A planet is a celestial body that (a) is by far the largest object in its local population[1], (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape [2], (c) does not produce energy by any nuclear fusion mechanism [3].
(2) According to point (1) the eight classical planets discovered before 1900, which move in nearly circular orbits close to the ecliptic plane are the only planets of our Solar System. All the other objects in orbit around the Sun are smaller than Mercury. We recognize that there are objects that fulfill the criteria (b) and (c) but not criterion (a). Those objects are defined as "dwarf" planets. Ceres as well as Pluto and several other large Trans-Neptunian objects belong to this category. In contrast to the planets, these objects typically have highly inclined orbits and/or large eccentricities.
(3) All the other natural objects orbiting the Sun that do not fulfill any of the previous criteria shall be referred to collectively as ?Small Solar System Bodies?.[4]
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question: notre planete, la Terre, n'a donc aucune activité nucléaire en son coeur ??
c'est une question: pas tapper