How many days are there in a year on Mars?

687 days. Its diameter is about 53% of the earth's and its mass is 14% of the earth's. Due to the axial tilt, the rotation period is similar to that of the earth, and one circle is about twice that of the earth. The orange appearance is the surface hematite (iron oxide).

In ancient books in China, Mars was called "the twinkling star", while in ancient western countries (ancient Rome) it was called "the mythical star of Mars". It is the only guardian star of Aries in the twelve constellations, not the guardian planet of Scorpio.

Extended data:

Mars is called the god of war in the west, perhaps because of its bright red color, so Mars is sometimes called the "red planet".

(Before the Greeks, the ancient Egyptians once worshipped Mars as a god of agriculture. Later, the ancient Greeks regarded Mars as Ares, while the ancient Romans inherited the Greek myth and called it "Mars Myth". In Norse mythology, Mars is Tyr, the god of war. And the name of March also comes from Mars. )

Mars was called "fluorescent star" in ancient China, because it is red and fluorescent like fire, which symbolizes fire in the five elements, and its brightness often changes; And in air movement, sometimes from west to east, sometimes from east to west, the situation is complicated and chaotic, so China called it "Yingying" in ancient times, which means "Yingying firelight, leaving chaos".

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