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Size and scale
Both the sizes of the planets and their distances from the Sun vary enormously. At its closest, Mercury is just 0.31 AU (or 46.5 million km) from the Sun whereas Pluto can be 7400 million km away. Similarly, Jupiter has a diameter of 142,800 km and tiny Pluto is a mere 2445 km across. For a given planet, the closest point to the Sun is perihelion and the most distant is aphelion. All of the planets are tiny compared with the distances between them.
The tables give basic information on the size of planets and their orbits.
The sidereal period is the time taken for the planet to return to the same place in its orbit, relative to the star background and inclination is the tilt of a planet's orbit with respect to the ecliptic plane.
Oblateness indicates how much a planet's shape departs from a sphere. In this case, the rotation periods listed are sidereal i.e. measured with respect to the star background. The axial tilt describes how far a planet's rotation axis leans away from the perpendicular to the ecliptic.
Unlike stars, the planets in our solar system shine by reflecting visible light from the Sun.
Questions to think about
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