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Solar System

Solar System

A photograph of the SunA photograph of the Sun The star we call the Sun lies at the centre of the Solar System, an array of objects of various sizes that move around, or orbit, it. These are: the eight major planets (in order of distance from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune), their moons, dwarf planets, the asteroids, comets, meteoroids and vast amounts of gas and dust. The Sun’s massive size, compared to the rest of its family, gives it the gravitational pull that keeps all the planets and other objects in perpetual orbit.


The planets orbit the Sun in the same anticlockwise direction and in elliptical paths (oval, rather than perfectly circular). Seven of the planets, and most of their moons, all travel roughly on the same plane. Mercury is the exception: it has a slightly tilted orbit. Pluto, now classified as a dwarf planet, lies in the Kuiper Belt, a vast region beyond the orbit of Neptune, the outermost planet. Pluto's orbit is significantly more tilted and elliptical than the true planets.

The planets' orbits around the SunThe planets' orbits around the SunThe relative distances of the planets from the SunThe relative distances of the planets from the Sun

The region between the Kuiper Belt and the Oort Cloud, called the Scattered Disc, is still almost completely unknown.  

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