Introduction to Mars
In ancient times, Mars was called "Ying", which was recorded in many ancient books. For example, "Historical Records Song Weizi Family", "In thirty-seven years, King Hui of Chu destroyed Chen. Mars stays in antares. "
Mars is one of the eight planets in the solar system, the fourth planet from the inside out, belonging to the earth-like planet. The diameter is about 53% of the earth, the mass is 1 1% of the earth, and the surface gravity is about 2/5 of the earth. Mars has two natural satellites: Phobos and Phobos, which are irregular in shape and may be isolated dwarf planets. On earth, Mars is visible to the naked eye, with the highest brightness reaching -2.9. Among the eight planets, it is darker than Jupiter and Venus.
Mars is about half the diameter of the earth, with a volume of 15% and a mass of 1 1%. Its surface area is equivalent to the land area of the earth, but its density is far less than that of the other three terrestrial planets (Mercury, Venus and Earth). In terms of radius, mass and surface gravity, Mars is about halfway between the earth and the moon. The diameter of Mars is about twice that of the moon and half that of the earth. Its mass is about 9 times that of the moon and19 of the earth, and its surface gravity is about 2.5 times that of the moon and 2/5 of that of the earth.