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Mercury

The closest planet to the Sun is a small, rocky world with extreme temperature variations. Its surface is heavily cratered, evidence of impacts from asteroids and comets.

Characteristics​

  • Size and Composition: Mercury is a rocky planet with a diameter of about 4,880 kilometers (3,032 miles), making it slightly larger than Earth's moon. Its surface is heavily cratered, evidence of numerous impacts from asteroids and comets.
  • Extreme Temperatures: Due to its proximity to the Sun, Mercury experiences extreme temperature variations. Surface temperatures can soar as high as 427 degrees Celsius (800 degrees Fahrenheit) during the day and plummet to -173 degrees Celsius (-280 degrees Fahrenheit) at night.
  • Orbital Characteristics: Mercury orbits the Sun at an average distance of about 0.39 astronomical units (AU) and completes one orbit approximately every 88 Earth days. Its orbit is the most eccentric of all the planets in the solar system, meaning it has the most elongated and elliptical shape.
  • Lack of Moons: Unlike most other planets, Mercury does not have any moons orbiting around it.

Facts​

Did you know...
  • No Atmosphere: Mercury has a very thin atmosphere composed mainly of trace amounts of hydrogen, helium, and oxygen. Its lack of a substantial atmosphere contributes to its extreme temperature differences between day and night.
  • Sparse Surface Features: In addition to impact craters, Mercury's surface features include extensive plains, scarps, and ridges. The planet's surface is also marked by large basins and valleys formed by ancient volcanic activity.
  • Spacecraft Exploration: Mercury has been visited by only two spacecraft: NASA's Mariner 10 and MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging). These missions have provided valuable data about the planet's surface, composition, and magnetic field.

Summary​

Despite its proximity to the Sun and harsh environmental conditions, Mercury remains an intriguing object of study for scientists seeking to understand the formation and evolution of rocky planets in the solar system.

Last updated on by Keith Tan