Mars
Humanity's next destination in the solar system
The Fourth Planet from the Sun
Overview
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries the name of the Roman god of war and is often referred to as the "Red Planet" due to its reddish appearance, which is caused by iron oxide (rust) on its surface.
Mars is a terrestrial planet with a thin atmosphere, with surface features reminiscent both of the impact craters of the Moon and the valleys, deserts, and polar ice caps of Earth.
The days and seasons on Mars are comparable to those of Earth, as the rotation period and axial tilt relative to the ecliptic plane are similar. A Martian day (sol) is 24 hours, 39 minutes, and 35 seconds long, and a Martian year is 687 Earth days.
Planetary Features
Mars is home to the largest volcano in the solar system, Olympus Mons, which is nearly three times the height of Mount Everest. It also has Valles Marineris, one of the largest canyons in the solar system, which stretches over 4,000 km (2,500 mi) long and reaches depths of up to 7 km (4.3 mi).
Average Temperature
Much colder than Earth's average
Surface Gravity
Of Earth's gravity
Day Length
Similar to an Earth day
Mars Exploration
Mars has been explored by numerous spacecraft, beginning with Mariner 4 in 1965. Since then, orbiters, landers, and rovers have studied the planet's surface, climate, and geology.
Perseverance
NASA's latest rover, searching for signs of ancient life and collecting samples for future return to Earth.
Curiosity
Exploring Gale Crater since 2012, analyzing Mars' climate and geology.
Ingenuity
The first aircraft to achieve powered, controlled flight on another planet.
Mission Highlight: Perseverance Rover
Landed in Jezero Crater on February 18, 2021, the Perseverance rover is searching for signs of ancient microbial life. It's collecting rock and soil samples that could be returned to Earth by future missions.
The rover also carries the Ingenuity helicopter, which has demonstrated that powered flight is possible in Mars' thin atmosphere, opening new possibilities for planetary exploration.
Fascinating Facts About Mars
Olympus Mons
The largest volcano in our solar system, standing 21 km (13 mi) high.
Water Ice
Mars has water ice at its poles and possibly in subsurface deposits.
Dust Storms
Mars can experience planet-wide dust storms that last for months.
Ancient Rivers
Evidence suggests Mars once had rivers, lakes, and possibly oceans.
The Moons of Mars
Mars has two small moons, Phobos and Deimos, which are thought to be captured asteroids. Both moons were discovered in 1877 by American astronomer Asaph Hall.
Phobos, the larger moon, orbits so close to Mars that it rises and sets twice each Martian day. It's gradually moving closer to Mars and will either crash into the planet or break up into a ring in about 50 million years.
Deimos, the smaller moon, has a more distant orbit and is gradually moving away from Mars. Both moons are irregularly shaped and heavily cratered.
Mars vs. Earth
While often called Earth's "sister planet," Mars is significantly different from our world:
Diameter: 6,779 km
Mass: 10.7% of Earth's
Gravity: 38% of Earth's
Diameter: 12,742 km
Mass: 5.97×10^24 kg
Gravity: 9.8 m/s²
Mars is about half the size of Earth and has a much thinner atmosphere composed mostly of carbon dioxide. While Earth has abundant liquid water, any water on Mars exists primarily as ice.
The Future of Mars
Mars is the focal point of much speculation and serious study about possible human colonization. NASA, SpaceX, and other organizations have proposed crewed missions to Mars, with timelines ranging from the 2030s to 2050s.
The challenges are significant - from the months-long journey through space to radiation exposure, the psychological effects of isolation, and creating sustainable habitats on the Martian surface.
Yet the potential rewards are equally significant - establishing a permanent human presence on another world, advancing scientific knowledge, and ensuring the long-term survival of our species by becoming a multi-planetary civilization.