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| | Nations Online - Earth Facts |
 | | The mean distance between Earth and the Sun is also used to indicate distances within a solar system, it is called Astronomical Unit, 1 AU = 149,597,870 km or 92,750,680 miles. |
 | | Planet Earth is made of stardust, born in the heat of a supernova together with the sun and the other planets. |
 | | Earth's spin axis is not perpendicular, the axis is tilted 23,45°, this circumstance causes the seasons, because Earth's surface changes its position relative to the Sun and therefore the amount of heat delivered to the surface. |
| www.nationsonline.org /oneworld/earth.htm (1822 words) |
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