Mars

Mars, once a potentially habitable planet, is now the focus of ambitious plans for human exploration.

Telescopic picture of planet Mars

Introduction

Mars, the fourth planet from the Sun, is a cold, desert world with a thin atmosphere. It's referred to as the Red Planet because iron-bearing dust on its surface becomes oxidized.

Properties

Property	Information
Physical Characteristics	Radius: 3,390 km (approximately half of Earth's) Distance from Sun: 228 million km (1.5 AU) Day Length: 24.6 hours (sols) Year Length: 687 Earth days
Seasons	Due to its 25° axial tilt, Mars experiences seasons like Earth, but more prolonged ones. Seasonal duration is irregular due to its elliptical orbit: Northern spring: 194 sols Northern summer: 178 sols Northern autumn: 142 sols Northern winter: 154 sols
Surface Features	Olympus Mons: The tallest volcano in the solar system (3× height of Everest) Valles Marineris: More than 4,800 km long canyon system Mars has ancient riverbeds, which signify a wetter past.
Moons	Mars has two irregular moons, Phobos and Deimos, which are likely to be captured asteroids. Phobos is gradually falling towards Mars and can form a dust ring in 50 million years.

Atmosphere and Climate

Mars' thin atmosphere consisting mainly of CO₂ results in extreme temperatures ranging from 20°C to -153°C. Dust storms may cover the entire planet.

Potential for Life

Mars likely once had liquid water. Researchers now seek microbial fossils or chemical traces of past life, especially in areas with evidence of water.

Scientific diagram of Mars

Summary

Mars is a cold, desert-like planet known as the Red Planet due to its iron-rich, oxidized dust. It's half the size of Earth and has a thin CO₂ atmosphere with temperatures ranging from 20°C to –153°C. A Martian day lasts 24.6 hours, and its year is 687 Earth days. Mars has seasons due to its tilted axis, but they’re longer and uneven because of its elliptical orbit. Surface features include Olympus Mons, the tallest volcano, and Valles Marineris, a vast canyon. Mars has two small moons, Phobos and Deimos, likely captured asteroids. While it’s too harsh for life now, signs of ancient riverbeds suggest it may once have had water and possibly microbial life.