Solar System

The solar system consists of the central sun and the celestial bodies orbiting it. There are eight planets, with Pluto recently reclassified as a dwarf planet. Six of the planets bind satellites, or moons, by their gravitational fields. Other major components are the Asteroid belt and the Oort cloud.

Fast Facts

1. The word "solar" is derived from the Latin word "sol," which means "sun"¹
2. Comprises 166 known moons¹
3. Comprises 4 dwarf planets¹
4. Divided in the "Inner Solar System" and the "Outer Solar System"¹
5. All of the planets' names, except Earth, originate from Greek and Roman mythology¹
6. Planets are categorized as either "terrestrial" and "gaseous"¹

Planets

There are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.² Astronomers categorize them according to their consistence, either as terrestrial or gaseous, and their distance from the sun, either as inner or outer.² The distance from the sun also determines the surface temperature and the year's length on each planet. Mercury, the closest planet to the sun, is also the hottest, with a year consisting of 88 Earth days. Neptune, the farthest planet, is also the iciest, with a year consisting of 164.79 Earth years.²

History and Discovery

Humanity did not believe in the existence of the solar system for millennia. Earth was considered the center of the universe, with the sun circling the planet.³ Only after the scientific discoveries of Nicholaus Copernicus, Galileo Galilei, Isaak Newton and Johannes Kepler, has the notion of a heliocentric system been accepted.³

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