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When the Sun, Earth, and the Moon are arranged in a straight line, the Moon can partially...
The diameter of the Sun is about 109 times that of the Earth. Most of its mass consists...
This animation demonstrates the geographical locations of the Earth's major cities.
An introduction to the relief and hydrography of China.
Domesticated animals and crops originate from various parts of the world.
The lesson introduces you to the movement of Earth around the Sun.
Saturn is the second largest planet in the Solar System, easily recognisable by its rings.
A presentation of the major administrative units of China.