Planet Facts
Planet Facts

Mercury Facts

Mercury is the planet nearest to the sun. It has a diameter of 3,031 miles, about two-fifths the Earth's diameter. Because of Mercury's size and nearness to the brightly shining sun, the planet is often hard to see from Earth without a telescope. The ancient Romans named it Mercury in honor of the swift messenger of their Gods.

Mercury Facts You Might Not Know About
  • Mercury has no moons
  • The sun appears two and a half times larger in Mercury's sky compared to the Earth's.
  • If you weigh 100 pounds on Earth, you would only weigh 37 pounds on Mercury.
  • Mercury has virtually no atmosphere. It however has small traces of an atmosphere which consists minute quantities of Hydrogen, Oxygen, Sodium, Potassium and argon.
  • Because of the lack of atmosphere, Mercury's sky is black and the stars probably can be seen during the day.
  • It takes less than 88 Earth days for Mercury to orbit around the sun.
  • Because of a lack of an atmosphere, the temperature rises above 800°F while on the dark side it falls rapidly to -300°F.
  • Mercury is the most iron rich planet in the Solar System with an iron core like Earth.
  • The surface of Mercury is heavily cratered, looking much like our moon.
  • Mercury rotates slowly on its axis. It completes one rotation every 59 Earth days.
  • As a result of the planet's slow rotation on its axis and rapid movement around the sun, a day on Mercury—that is, the interval between one sunrise and the next—lasts about 180 Earth days.
  • The sun's rays are about seven times as strong on Mercury as they are on the Earth.

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