Satellites.Satellites. Satellites.
Satellite - is an object, which has been placed into orbit by human endeavor. Satellite - is an object, which has been placed into orbit by human endeavor.
Satellites: Natural Natural Artificial Artificial
Natural satellites: The Moon. The Moon. The Phobos and the Deimos. The Phobos and the Deimos.
Artificial satellites. Sputnik 1. Sputnik 1. Explorer 1 Explorer 1
The first artificial satellite was Sputnik 1. It was launched by the Soviet Union on the 4th of October 1957.
A few hundred satellites and thousand of unused satellites are orbiting the Earth.
Purposes: Military observation Military observation Communication Communication Navigation Navigation Weather forecast Weather forecast Researches Researches