Planet Mercury

Mercury is the smallest and closest planet to the Sun. It is actually smaller than two of the Solar System’s moons—Ganymede (Jupiter) and Titan (Saturn). Because Mercury has no real atmosphere, it has extreme high and low temperatures. Examining the planet, Mercury looks a lot like the Moon.

Image of Mercury.
MercuryPublic Domain | Image courtesy of NASA / JPL-CALECH.

Planet Mercury at a Glance

Characteristic – Current State

  • Impact Craters – Yes
  • Tectonic Craters – Yes; not active
  • Volcanoes – Yes; not active
  • Atmosphere – No real atmosphere
  • Water – Yes; water and ice in craters at the poles
  • Erosion – No
  • Dunes – No
  • Polar Caps – No
  • Satellites – No
  • Life – Unknown
Image of Mercury's surface and craters.
Craters on MercurynCC BY 2.0 | Image courtesy of NASA Goddard Space Flight Center from Greenbelt, MD, USA.