solar system summary

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Below is the article summary. For the full article, see solar system.

solar system to scaleThe eight planets of the solar system and Pluto, in a montage of images scaled to show the approximate sizes of the bodies relative to one another. Outward from the Sun, which is represented to scale by the yellow segment at the extreme left, are the four rocky terrestrial planets (Mercury, Venus, Earth, and Mars), the four hydrogen-rich giant planets (Jupiter, Saturn, Uranus, and Neptune), and icy, comparatively tiny Pluto.

solar system, The Sun, its eight major planets, the dwarf planets and small bodies, and interplanetary dust and gas under the Sun’s gravitational control. Another component of the solar system is the solar wind. The Sun contains more than 99% of the mass of the solar system; most of the rest is distributed among the planets, with Jupiter containing about 70%. According to the prevailing theory, the solar system originated from the solar nebula. See also asteroid; Centaur object; Ceres; comet; Earth; Eris; Jupiter; Kuiper belt; Mars; Mercury; meteorite; Neptune; Oort cloud; Pluto; Saturn; Uranus; Venus.

Halley’s Comet Summary

Halley’s Comet, the first comet whose return was predicted and, almost three centuries later, the first to be imaged up close by interplanetary spacecraft. In 1705 English astronomer Edmond Halley published the first catalog of the orbits of 24 comets. His calculations showed that comets observed

Triton Summary

Triton, largest of Neptune’s moons, whose unusual orbital characteristics suggest that it formed elsewhere in the solar system and was later captured by Neptune. It was discovered by the English astronomer William Lassell in October 1846, only a few weeks after the discovery of Neptune itself.

Titan Summary

Titan, the largest moon of Saturn and the only moon in the solar system known to have clouds and a dense atmosphere. It is the only body other than Earth that is known to currently have liquid on its surface. It was discovered telescopically in 1655 by the Dutch scientist Christiaan Huygens—the

Kuiper belt Summary

Kuiper belt, flat ring of icy small bodies that revolve around the Sun beyond the orbit of the planet Neptune. It was named for the Dutch American astronomer Gerard P. Kuiper and comprises hundreds of millions of objects—presumed to be leftovers from the formation of the outer planets—whose orbits