7 résultats pour "phobos"
- PHOBOS
- Phobos.
- Phobos (space program) - astronomy.
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Asteroid - astronomy.
Asteroids of the S type, related to the stony iron meteorites, make up about 15 percent of the total population of asteroids that can be seen from Earth. Much rarer arethe M-type objects, corresponding in composition to the meteorites known as “irons.” These objects are made up of an iron-nickel alloy and may represent the cores ofbodies that were large enough to differentiate into layers and to melt deep inside. Their rocky outer layers may have been removed by impacts with other asteroids . A...
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DES SATELLITES NATURELS.
LES SATELLITES INTERNES Adrastée, Métis , Amalthée et Thébé évoluent à l'intérieur de l'orb ite de la. De faibles dimensions (moins de 100 km de diamètre), ces lunes sont probablement les sources de poussière qui alimentent les anneaux de Jupiter. LES SATELLITES SATURNIENS Les lunes de Saturne portent les noms de titans et de leur descendance, de dieux romains primitifs, et de géants greco-romains, inuits, scandinaves et gaéliques. Dans la mythologie...
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Natural Satellite - astronomy.
Titan, Saturn’s largest moon, also has few impact craters. Although icy volcanism from water and ammonia may occur along with some tectonic activity, Titan’s youngsurface is most likely the result of weather processes. Titan’s dense, cold atmosphere precipitates particles of complex organic molecules that accumulate as dunes andmountains. Methane rain erodes the surface and creates lakes at the moon’s poles. Triton’s young surface also may result from processes in its atmosphere, as well aserupt...
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Mars (planet) - astronomy.
The Martian core is probably much like Earth’s, consisting mostly of iron, with a small amount of nickel. If other light elements, particularly sulfur, exist there as well, thecore may be larger than presently thought. From studying Earth’s magnetic field and core, scientists theorize that the motions of the liquid rock in Earth’s core generateits magnetic field. Mars does not have a significant magnetic field, so scientists believe that Mars’s core is probably solid. However, spacecraft data in...