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The Romans named Mercury after the fleet-footed messenger of the gods because it appeared to move across the sky faster than any other planet. In mythology, Mercury is the god of travel, commerce and thievery, and is counterpart to the Greek god Hermes.
Historically, Mercury has been observed all the way back to the Sumerians of 3rd millennium BC and also the Greeks who have given the planet two names: Apollo and Hermes: Apollo for its appearance in the early morning while Hermes as the evening star.
Mercury is the eighth largest planet (second smallest) in the solar system and the closest to the Sun. It is smaller than Jupiter's moon Ganymede and Saturn's moon, Titan (but more massive). In its size, Mercury is 40% smaller than Earth and 40% larger than our Moon.
Mercury is also known to have one of the most extreme temperature (90 K to 700 K) ranges due in large part to its closeness to the Sun and almost complete lack of atmosphere to regulate constant temperature. It is also the second hottest planet (Venus is the first) and has an extremely eccentric orbit.It has an orbit of 57,910,000 kilometers (0.38 AU) from the Sun. The planet has a diameter of 4,880 kilometers and a mass of 3.30e23 kg.
Mercury Site Contents
- Introduction to Mercury
- Formation of Mercury
- Exploration