Random Facts About Mars

All Mars Facts

• Mars is named after the Roman god of war, likely because its reddish color reminded ancient observers of blood.
• Ancient Egyptians called Mars "Her Desher," meaning "the red one," thousands of years before telescopes existed.
• A day on Mars, called a "sol," lasts about 24 hours and 37 minutes, only slightly longer than a day on Earth.
• A year on Mars lasts about 687 Earth days, almost twice as long as an Earth year.
• Mars has a diameter of about 4,220 miles (6,779 km), roughly half the diameter of Earth.
• Mars's gravity is about 38% of Earth's, so a 150-pound person would weigh only about 57 pounds there.
• Even though Mars is much smaller than Earth, its total land surface area is roughly comparable to Earth's, since Mars has no oceans.
• Mars orbits the Sun at an average distance of about 142 million miles (228 million km).
• At its closest recorded approach in 2003, Mars came within about 34.6 million miles of Earth, the nearest in nearly 60,000 years.
• Mars's axial tilt of about 25 degrees is close to Earth's, which is why it has four seasons much like our planet.
• Because a Martian year is so much longer than Earth's, each Martian season lasts roughly twice as long as its Earth counterpart.
• Mars's orbit is noticeably more elliptical than Earth's, so its distance from the Sun varies more sharply over the Martian year.
• Mars's atmosphere is about 95% carbon dioxide, with only trace amounts of oxygen and water vapor.
• The atmospheric pressure on Mars is less than 1% of Earth's, too thin to support liquid water on the surface today.
• Because Mars's atmosphere is so thin, it traps very little heat, causing huge temperature swings between day and night.
• Temperatures near the Martian poles can plunge to about -195°F (-125°C) in winter.
• On a warm summer day near the Martian equator, temperatures can briefly reach around 70°F (20°C).
• Daytime skies on Mars often appear butterscotch or reddish, tinted by fine iron oxide dust suspended in the thin atmosphere.
• Sunsets on Mars can look bluish, the opposite of Earth, because Martian dust scatters light differently than our atmosphere does.
• Mars does not have a global magnetic field today, though patches of magnetized rock in its crust show it once did billions of years ago.
• Scientists think the loss of Mars's magnetic field let solar wind gradually strip away most of its once-thicker atmosphere.
• Olympus Mons, the largest volcano on Mars, stands about 13.6 miles (22 km) high, nearly three times the height of Mount Everest.
• Olympus Mons is so wide at its base that it would cover an area roughly the size of the state of Arizona.
• Olympus Mons is a shield volcano, built up gradually by countless lava flows rather than a single explosive eruption.
• Three more giant volcanoes, Arsia Mons, Pavonis Mons, and Ascraeus Mons, line up in a row on Mars's Tharsis plateau.
• Valles Marineris, a canyon system on Mars, stretches roughly 2,500 miles long, nearly the width of the continental United States.
• In places, Valles Marineris plunges as deep as 4.3 miles (7 km), more than seven times deeper than Earth's Grand Canyon.
• Hellas Planitia is a massive impact basin on Mars, one of the largest confirmed impact craters in the entire solar system.
• Mars has two polar ice caps that grow and shrink with the seasons as frozen carbon dioxide comes and goes.
• Beneath its seasonal frost, Mars's northern polar cap holds a thick layer of water ice.
• Mars's southern polar cap keeps a permanent layer of frozen carbon dioxide, often called "dry ice," year-round.
• Mars has clouds too, made of water ice or, at times, of frozen carbon dioxide crystals.
• Dust devils, small spinning columns of wind and dust, regularly sweep across the Martian surface and have even been photographed from orbit.
• Mars occasionally experiences planet-encircling dust storms so vast they can block sunlight across the entire globe for weeks.
• A global dust storm in 2018 blotted out so much sunlight that it silenced NASA's solar-powered Opportunity rover for good.
• Global Martian dust storms tend to strike during southern hemisphere summer, when Mars is closest to the Sun in its elliptical orbit.
• The Martian south pole is home to strange "spider" patterns in the ground, carved as trapped carbon dioxide ice turns directly to gas each spring.
• Mars has two small moons, Phobos and Deimos, both thought to be either captured asteroids or debris from an ancient impact.
• Phobos and Deimos are named after the sons of Ares, the Greek god of war, whose names mean "fear" and "dread."
• Phobos orbits Mars so quickly, about three times a day, that it appears to rise in the west and set in the east.
• Phobos is slowly spiraling inward toward Mars and is expected to eventually break apart or crash into the planet within tens of millions of years.
• Deimos, the smaller and more distant of Mars's two moons, is lumpy and irregularly shaped rather than round.
• Neither Martian moon is large enough for its own gravity to pull it into a spherical shape.
• Ancient river channels and fan-shaped deltas etched into the Martian surface suggest liquid water once flowed there in abundance.
• Some scientists believe Mars's northern lowlands may once have held a vast ocean, billions of years before the planet dried out.
• NASA's Opportunity rover found small mineral spheres nicknamed "blueberries," made of hematite that typically forms in the presence of water.
• NASA's Phoenix lander confirmed water ice just beneath the Martian soil near the north pole in 2008.
• Radar studies have detected large deposits of water ice hidden underground across many regions of Mars.
• Dark streaks called recurring slope lineae appear and grow on some Martian crater walls during warm seasons, though scientists still debate whether they involve any liquid water.
• Gullies carved into some Martian crater walls hint that liquid water, or perhaps carbon dioxide frost, may still shape the surface occasionally today.
• NASA's Curiosity rover has detected organic molecules, the carbon-based building blocks of life, preserved in ancient Martian rocks.
• Curiosity has also measured methane in the Martian atmosphere that mysteriously rises and falls with the seasons, and its source is still unknown.
• In 2021, the Perseverance rover's MOXIE instrument successfully produced breathable oxygen from Mars's carbon dioxide atmosphere for the first time.
• NASA's InSight lander detected marsquakes on Mars, revealing that the planet still has a molten, at least partly liquid, core.
• Seismic data from InSight suggests Mars's core has a radius of roughly 1,140 miles, larger than scientists had previously estimated.
• Mariner 4 became the first spacecraft to fly past Mars in 1965, returning the first close-up images ever taken of another planet.
• Mariner 9 became the first spacecraft to orbit another planet when it reached Mars in 1971.
• The Soviet Mars 3 mission achieved the first soft landing on Mars in 1971, but its lander transmitted for only about 20 seconds before falling silent.
• NASA's Viking 1 became the first fully successful lander on Mars in 1976, operating on the surface for more than six years.
• The Viking landers carried out experiments specifically designed to search for microbial life in Martian soil, though results were inconclusive.
• So many early Mars missions failed that space enthusiasts nicknamed the run of bad luck the "Great Galactic Ghoul."
• Roughly half of all Mars missions ever attempted, across every space agency, have ended in partial or total failure.
• NASA lost its Mars Climate Orbiter in 1999 after one engineering team used metric units and another used imperial units for the same calculations.
• The British Beagle 2 lander was presumed lost after its 2003 landing, until orbital images found it intact on the surface more than a decade later.
• Sojourner, the first rover to operate on Mars in 1997, was roughly the size of a microwave oven.
• NASA's Spirit and Opportunity rovers landed on Mars in 2004, each designed for a 90-day mission.
• Opportunity kept exploring Mars for almost 15 years before a global dust storm finally ended communication with it in 2018.
• Spirit became stuck in soft Martian soil in 2009 and eventually stopped communicating with Earth in 2010.
• Curiosity, roughly the size of a small car, landed inside Mars's Gale Crater in 2012 using a rocket-powered "sky crane."
• Curiosity's main science target, Mount Sharp, is a layered mountain of sediment rising from the floor of Gale Crater.
• Both Curiosity and Perseverance run on nuclear power from a radioisotope generator, letting them keep working without relying on sunlight.
• Earlier solar-powered rovers like Spirit and Opportunity gradually lost power as dust settled on their solar panels over time.
• NASA's Perseverance rover landed in Jezero Crater in 2021, a site chosen because it holds the remains of an ancient river delta.
• Perseverance is drilling and caching rock samples on Mars for a future mission designed to bring them back to Earth for study.
• Perseverance carries microphones that have recorded the actual sound of Martian wind and the rover's own mechanical clicks and whirs.
• Because Mars's atmosphere is thin and mostly carbon dioxide, sound there travels more quietly and higher-pitched tones fade out faster than on Earth.
• In April 2021, NASA's Ingenuity helicopter made the first powered, controlled flight ever achieved on another planet.
• Ingenuity had to spin its rotor blades far faster than any helicopter on Earth to generate lift in Mars's thin atmosphere.
• Ingenuity flew 72 flights on Mars before rotor damage grounded it for good in early 2024, far outlasting its planned five-flight test campaign.
• China's Zhurong rover touched down on Mars in 2021 as part of the Tianwen-1 mission, making China only the second country to land and operate a rover there.
• The United Arab Emirates' Hope probe entered orbit around Mars in 2021, becoming the first Mars mission led by an Arab nation.
• The European Space Agency's Mars Express orbiter has been studying the planet continuously since 2003.
• NASA's Mars Reconnaissance Orbiter carries the HiRISE camera, sharp enough to spot surface features smaller than a yard across from orbit.
• More than 300 meteorites found on Earth have been identified as originating from Mars, blasted into space by ancient asteroid or comet impacts.
• A Martian meteorite found in Antarctica in 1984, known as ALH84001, once sparked controversy when some scientists suggested it held fossilized microbial life, a claim now widely disputed.
• Mars has at least five known trojan asteroids, small bodies that share its orbit around the Sun.
• Mars is bright enough to see with the naked eye from Earth and has been observed by skywatchers since ancient times.
• Babylonian astronomers associated Mars with Nergal, their god of war and plague, thousands of years ago.
• In Hindu astrology, Mars is known as Angaraka or Mangala and is tracked as one of the classical navagraha bodies.
• Mars's puzzling retrograde motion in the night sky, appearing to move backward at times, helped inspire ancient debates that eventually led to the heliocentric model of the solar system.
• A trip to Mars with current propulsion technology takes roughly seven months one way.
• Because Mars and Earth orbit the Sun at different speeds, launch windows to Mars only open up roughly once every 26 months.
• NASA and other agencies are studying future crewed missions to Mars, though no human has yet set foot on the planet.
• SpaceX has designed its Starship rocket with the long-term goal of eventually carrying astronauts and cargo to Mars.
• Researchers use extreme places on Earth, like Antarctica's Dry Valleys and Chile's Atacama Desert, as stand-ins for testing Mars exploration technology and searching for life in Mars-like conditions.
• Because Mars lacks an ozone layer, its surface receives far more damaging ultraviolet radiation than Earth's does.
• Mars's thin atmosphere and lack of a magnetic field mean the surface is also bathed in more cosmic radiation than Earth, a major challenge for future astronauts.
• Mars has no moons large enough to stabilize its axial tilt the way Earth's Moon does, so its tilt is thought to have wandered more dramatically over millions of years.
• Mars's iconic red-orange color comes from iron oxide, essentially rust, coating fine dust across most of its surface.
• Beneath its rusty dust, much of the actual bedrock on Mars is grey or black basalt, similar to volcanic rock found on Earth.
• Some regions of Mars, like the Medusae Fossae Formation, are covered in soft, easily eroded material that wind has carved into strange ridges and grooves.
• Mars's craters range from tiny pits to Hellas Planitia, which measures roughly 1,300 miles across.
• Mars is a favorite target for amateur astronomers because it can be viewed through a modest backyard telescope during its closest approaches to Earth.
• Mars has surface gravity of about 3.72 meters per second squared, well under half of Earth's 9.8.
• A Martian year lasts roughly 668 to 669 Martian sols, even though it equals about 687 Earth days.
• The Perseverance rover's landing site, Jezero Crater, was once filled by a lake fed by a river that deposited a fan-shaped delta still visible today.
• Mars's two moons are so small that Phobos is only about 14 miles across and Deimos just 7.7 miles across at their longest points.
• Because Deimos orbits so far out and slowly, it would appear from the Martian surface as little more than a bright, star-like point of light.
• The word "areology" is sometimes used for the geological study of Mars, borrowing from Ares, the Greek name for the god of war.
• Mars has been visited or observed by robotic missions from the United States, the Soviet Union/Russia, Europe, India, China, Japan, and the United Arab Emirates.

Explore by Category

Dive into a topic and get random facts on demand.