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Solar System Facts

Solar System (or planets) Key Facts and properties.


  • There are 8 Planets in orbit around the Sun.

  • Mercury is the closest, and Neptune is the outermost Planet in the Solar System.

  • The further a Planet is from the Sun, the slower it travels, and the more time it takes to complete an orbit.

  • The further the Planet is from the Sun, the lower its average surface temperature. Except for Venus, where 97% Carbondioxide in the atmosphere causes severe greenhouse effect, and makes Venus the hottest Planet in the Solar System.

  • Mercury is the smallest, and Jupiter is the largest Planet in the Solar System.

  • The axis of rotation of Earth is tilted by 23.5o, and the axis of rotation of Uranus is tilted at more than 90o.