What are facts about mars and mercury?

Answer 1

Both planets are visible as bright points of light in the sky. Ancient astronomers called them "planets" because they appeared as "wandering stars" among the relatively stable backdrop of actual stars.

Both are rocky planets like Earth, but both are much smaller. Mercury is about 2/5 (38%) the size of Earth and Mars is about 1/2 the size (53%) of Earth.

Mercury is the closest planet orbiting the Sun. Mars is the 4th planet from the Sun. Mercury orbits the Sun every 88 Earth days, while Mars takes about 687 Earth days (1.8 years).

Mars has a relatively thin atmosphere of carbon dioxide. Mercury has virtually no atmosphere.

Mars has been visited by scientific probes from Earth, which have found no Earth-type life there, and very little water anywhere in the soil. Mercury may have water ice in craters near its poles, but no air and therefore no oxygen to support life.

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