What is Mars?

Overview

Mars, the Red Planet, is the fourth planet from the Sun, known for its reddish hue caused by iron oxide (rust) on its surface. It's a rocky, terrestrial world with a thin atmosphere.

  • Diameter: 6,792 km
  • Distance from Sun: 228 million km
  • Mass: 6.42 x 10²³ kg
  • Orbit Period: 687 days
  • Rotation Period: 24.62 hours
Mars from Mars Reconnaissance Orbiter

Image credit: NASA/JPL-Caltech

Details

Atmosphere: Thin, mostly carbon dioxide (95%), with traces of nitrogen and argon—too sparse to support human breathing.

Moons: Two small moons, Phobos and Deimos, likely captured asteroids with irregular shapes.

Surface: Home to Olympus Mons, the solar system's largest volcano, and Valles Marineris, a canyon stretching over 4,000 km.

Exploration: Explored by rovers like Curiosity and Perseverance, which search for signs of past water and life.

Fun Fact: Mars' red color comes from iron-rich dust, and it once had flowing rivers, now dry.