96 Fun Facts About Mars

What gives Mars its distinctive reddish appearance?

Mars appears red because its surface is covered in iron oxide, commonly known as rust. Iron minerals in the Martian soil oxidized billions of years ago, giving the planet its iconic reddish hue visible even from Earth.

What is the name of the tallest volcano on Mars, and the tallest known volcano in the solar system?

Olympus Mons rises about 21.9 km (13.6 miles), roughly 2.5 times the height of Everest, and is approximately tied with Rheasilvia on the asteroid Vesta as the tallest mountain yet found in the solar system.

Approximately how long is a Martian day (sol)?

A Martian day, called a sol, lasts approximately 24 hours and 37 minutes. This is remarkably close to Earth's 24-hour day, making Mars one of the most Earth-like planets in terms of day length.

Which canyon system along the Martian equator runs more than 4,000 km, about ten times the length of the Grand Canyon?

Valles Marineris stretches over 4,000 km along the Martian equator, about ten times longer and five times deeper than the Grand Canyon, the largest known canyon in the solar system.

Mars's mean surface air pressure is roughly what fraction of Earth's sea-level pressure?

The thin Martian air averages about 0.6% of Earth's sea-level pressure, close to the triple point of water, so liquid water on the surface would boil or freeze almost at once.

Which spacecraft became the first ever to orbit another planet when it reached Mars in November 1971?

Mariner 9 beat the Soviet Mars 2 and Mars 3 probes by only weeks, then had to wait out a months-long dust storm before it could send back clear pictures of the surface.

Which is the larger of Mars's two moons?

Phobos, about 22 km across, is nearly twice the diameter of Deimos and orbits so close to Mars that it rises in the west and sets in the east roughly every 11 hours.

What is the approximate surface gravity on Mars compared to Earth?

Mars has about 38% of Earth's surface gravity (3.72 m/s² vs 9.81 m/s²). A person weighing 100 kg on Earth would weigh only about 38 kg on Mars, though their mass remains the same.

What is the primary component of Mars's atmosphere?

Mars's atmosphere is about 96% carbon dioxide, with roughly 1.9% each of argon and nitrogen and only traces of oxygen and water vapour. It is also extremely thin, less than 1% of Earth's surface pressure.

What is the Hellas Planitia on Mars?

Hellas Planitia is one of the largest impact craters in the solar system, with a diameter of about 2,300 km and a depth of over 7 km. It was formed by an asteroid impact roughly 4 billion years ago and is located in Mars's southern hemisphere.

Which NASA rover famously operated for over 14 years on Mars, far exceeding its planned 90-day mission?

Opportunity landed on Mars in January 2004 for a planned 90-day mission but continued operating until June 2018 — over 14 years. A massive dust storm finally ended communications. It traveled over 45 km across the Martian surface.

What is the name of the helicopter drone that flew on Mars as part of the Perseverance mission?

Ingenuity was a small helicopter that made the first powered, controlled flight on another planet on April 19, 2021. Originally designed for 5 flights, it completed 72 flights before its mission ended in January 2024.

In which Martian crater did the Curiosity rover land in 2012?

Curiosity landed in Gale Crater on August 6, 2012. The crater contains Mount Sharp (Aeolis Mons), a 5.5 km high mound of layered sediment that scientists study to understand Mars's geological history.

Which lander, the first to complete a successful mission on Mars, touched down on July 20, 1976?

Viking 1 touched down in Chryse Planitia on 20 July 1976 and operated for more than six years, returning the first clear photographs from the Martian surface.

What was the name of the small rover carried by the Mars Pathfinder mission in 1997?

Sojourner was the first rover to operate on Mars, arriving as part of the Mars Pathfinder mission on July 4, 1997. It was about the size of a microwave oven and operated for 83 sols, analyzing rocks near its landing site.

In which crater did NASA's Perseverance rover land in 2021?

Perseverance landed in Jezero Crater on February 18, 2021. Scientists chose this location because it contains an ancient river delta, making it an ideal place to search for signs of past microbial life.

Which Perseverance experiment made oxygen from the air of Mars?

MOXIE (Mars Oxygen In-Situ Resource Utilization Experiment) showed that breathable oxygen can be pulled straight out of the thin Martian air, a step toward making air and rocket propellant for future crews.

Which Mars mission discovered that the planet once had a thicker atmosphere stripped away by solar wind?

NASA's MAVEN (Mars Atmosphere and Volatile Evolution) mission, which arrived at Mars in 2014, determined that solar wind and radiation stripped away Mars's atmosphere over billions of years, transforming it from a warm, wet world to the cold desert we see today.

Which twin rovers made up NASA's Mars Exploration Rover mission?

Spirit and Opportunity landed three weeks apart on opposite sides of the planet in January 2004; built for 90 days, Spirit worked until 2010 and Opportunity until 2018.

What did NASA's Phoenix lander discover just below the Martian surface in 2008?

The Phoenix lander, which touched down near Mars's north pole in May 2008, confirmed the presence of water ice just centimeters below the surface. The ice was observed to sublimate (turn directly from solid to gas) over several days after being exposed.

What evidence suggests Mars once had liquid water on its surface?

Orbital images show outflow channels carved by catastrophic floods, branching valley networks, deltas and lakebeds, while rovers have found clays and sulfates that only form in liquid water.

What is the contrast between Mars's low northern plains and cratered southern highlands called?

The Martian dichotomy is the split between low, smooth northern plains and the heavily cratered southern highlands; one leading idea is that a giant early impact formed the northern Borealis basin, covering about 40% of Mars.

What is the average surface temperature on Mars?

A commonly quoted average is about -63°C (-81°F). Temperatures swing from around -140°C at the winter poles to about 20°C at the equator in summer, because the thin air retains little heat.

What kind of ice forms the permanent surface of Mars's southern polar cap?

The southern cap keeps a permanent dry-ice cover about 8 metres thick, while the northern cap's surface is mostly frozen water. Beneath the southern dry ice lies a far larger store of frozen water.

Roughly how many of our years pass during a single Martian year?

A Martian year lasts about 687 Earth days, or approximately 1.88 Earth years. This is because Mars orbits farther from the Sun than Earth and therefore takes longer to complete one orbit.

What seasonal phenomenon occurs at Mars's poles that has no equivalent on Earth?

Each winter carbon dioxide freezes onto the poles as CO2 snow and dry ice; in spring it sublimates from below and geysers of gas and dark sand burst through, leaving fan-shaped deposits and spider-like channels.

In Babylonian astronomy, the planet Mars was named for which deity?

Nergal was a deity of war, plague and destruction, so the blood-red planet was linked to warfare long before the Romans named it for their own war god.

The names of Mars's two moons come from Greek words meaning what?

Phobos and Deimos are Greek for Fear and Dread; in myth they were twin sons of the war god and rode with him into battle.

Who discovered Mars's two moons in 1877?

Hall found both moons in August 1877 with the 26-inch refractor at the U.S. Naval Observatory in Washington, D.C., and nearly gave up the search before his wife encouraged him to continue.

Which astronomer built an Arizona observatory to map 'canals' on Mars that did not exist?

Lowell built an Arizona observatory and mapped elaborate canals in the 1890s-1900s, reading Schiaparelli's 'canali' (channels) as the work of an intelligent civilization.

What is the Greek equivalent of the Roman god Mars?

Ares is the Greek counterpart of Mars; while the Romans revered Mars as a dignified guardian of the city, the Greeks portrayed Ares as a brutal, unpopular figure among the Olympians.

What was the 'Face on Mars' that caused a media sensation?

A NASA orbiter photographed a mesa in the Cydonia region in 1976 that resembled a human face because of low resolution and shadow. Sharper images from later missions showed an ordinary eroded mesa, but the picture fed decades of conspiracy theories.

Which H.G. Wells novel features a Martian invasion of Earth?

The War of the Worlds, published in 1898, describes a devastating Martian invasion of England. Orson Welles's 1938 radio adaptation famously caused panic among listeners who believed it was a real news broadcast.

In the 2015 film 'The Martian,' how does stranded astronaut Mark Watney feed himself?

In Andy Weir's novel and Ridley Scott's film adaptation, stranded astronaut Mark Watney (played by Matt Damon) grows potatoes by mixing Martian soil with human feces as fertilizer and using water he creates through chemistry. The science is largely considered plausible by NASA.

Which author wrote 'The Martian Chronicles,' a classic collection of stories about Mars colonization?

Ray Bradbury published The Martian Chronicles in 1950. The book is a collection of interconnected short stories about humanity's colonization of Mars, the displacement of its native inhabitants, and the eventual destruction of Earth. It is considered one of the greatest works of science fiction.

What ore is mined on Mars in the 1990 film 'Total Recall'?

Vilos Cohaagen's monopoly on turbinium would end if the buried alien reactor made the air breathable. The film loosely adapts Philip K. Dick's 'We Can Remember It for You Wholesale'.

Which 1971 David Bowie album includes the song 'Life on Mars?'?

'Life on Mars?' is the fourth track on Hunky Dory, released in December 1971 and recorded at London's Trident Studios with co-producer Ken Scott; Bowie wrote it as a riposte to Sinatra's 'My Way'.

Kim Stanley Robinson's 1990s Mars trilogy takes its titles from which three colors?

Red Mars (1992), Green Mars (1993) and Blue Mars (1996) follow the planet from its natural state through the spread of plant life to open water and a breathable sky.

On a minimum-energy Hohmann transfer, the cheapest route, roughly how long does a one-way trip from Earth to Mars take?

About 9 months each way on a Hohmann transfer, and a crew would then wait roughly 500 days on Mars for the planets to realign, making the round trip nearly three years.

What is the 'launch window' for missions to Mars, and how often does it occur?

Optimal launch windows to Mars occur approximately every 26 months (about 2 years and 2 months), when Earth and Mars are in favorable alignment. This is why Mars missions tend to launch in clusters — multiple space agencies take advantage of the same window.

What does 'terraforming' mean in discussions of settling the red planet?

Terraforming means engineering an Earth-like environment by deliberately altering Mars's atmosphere, temperature and ecology so humans could live without spacesuits; proposed methods include releasing greenhouse gases and melting the polar caps.

What major challenge does cosmic radiation pose for astronauts traveling to Mars?

Without Earth's protective magnetic field and thick atmosphere, Mars-bound astronauts would be exposed to galactic cosmic rays and solar particle events. This radiation increases cancer risk, can damage the central nervous system, and may cause cognitive impairment — it is considered one of the biggest obstacles to human Mars missions.

What is the communication delay between Earth and Mars?

Radio signals traveling at the speed of light take between 3 and 22 minutes to travel between Earth and Mars, depending on the planets' relative positions. This means round-trip communication can take up to 44 minutes, making real-time control of rovers impossible.

Why does methane in Mars's atmosphere excite scientists?

On Earth most methane comes from living things; on Mars it could also come from serpentinization of olivine with water and CO2, so the Curiosity and Mars Express detections are tantalising but unproven.

What is Mars's position from the Sun in our solar system?

Mars is the fourth planet from the Sun, orbiting at an average distance of about 228 million km (142 million miles). It sits between Earth (third) and Jupiter (fifth) in the solar system.

What type of planet is Mars classified as?

Mars is a terrestrial or rocky planet, along with Mercury, Venus, and Earth. These inner planets are characterized by solid rocky surfaces, in contrast to the gas giants (Jupiter, Saturn) and ice giants (Uranus, Neptune) of the outer solar system.

Which mineral, found by a Mars rover as 'blueberries', points to long-lived water?

The rover exploring Meridiani Planum found countless grey hematite spherules, nicknamed 'blueberries', whose formation required acidic, salty liquid water flowing over the plain across two geological epochs.

Which country became the first Asian nation to successfully orbit Mars?

India's Mars Orbiter Mission (Mangalyaan), launched by ISRO, successfully entered Mars orbit on September 24, 2014. India became the first Asian nation — and the first nation in the world — to reach Mars orbit on its first attempt, at a remarkably low cost of about $74 million.

Which 1965 probe returned the first close-up pictures of the Martian surface?

Mariner 4 flew past Mars in July 1965 and returned the first 21 close-up images; impatient engineers hand-coloured a printout of the raw pixel numbers with pastels before the computer finished processing the first one.

China's Tianwen-1 mission takes its name from a poem by which ancient writer?

Tianwen, 'Heavenly Questions', is a long poem by Qu Yuan, the Warring States poet also honoured by the Dragon Boat Festival; Tianwen-1 entered Mars orbit in February 2021 and landed the Zhurong rover that May.

China's Zhurong rover is named after a mythological figure associated with what?

Zhurong is the god of fire in Chinese mythology, a fitting choice because Mars is Huoxing, 'the fire star', in Chinese; the name won a public vote ahead of the May 2021 landing.

The UAE's first Mars orbiter, which arrived in February 2021, launched from which country?

The Hope probe lifted off from Tanegashima, Japan, on a Mitsubishi H-IIA rocket in July 2020 and entered Mars orbit on 9 February 2021, the first interplanetary mission by an Arab nation.

What caused the loss of NASA's Mars Climate Orbiter in 1999?

Ground software reported thruster impulse in pound-force seconds while the navigation software expected newton-seconds, an error of a factor of 4.45.

Which British band composed the call sign for the Beagle 2 Mars lander?

Blur composed the call-sign tune Beagle 2 was to transmit after landing; the lander, named for Darwin's ship HMS Beagle, carried a camera test card painted by Damien Hirst.

Which ESA orbiter's radar found a subglacial lake under the planet's south pole in 2018?

Mars Express's MARSIS radar detected a bright reflector about 1.5 km beneath the south polar ice in 2018, interpreted as a lake of salty liquid water, though later studies proposed clays or other explanations.

Roughly how long does Phobos take to complete one orbit of Mars?

About 7 hours 39 minutes: Phobos orbits faster than Mars rotates, so from the surface it rises in the west and sets in the east roughly twice a day.

What do tidal models predict will eventually happen to Mars's larger moon?

Tidal drag is pulling the rubble-pile moon inward; the resulting ring might last anywhere from 1 million to 100 million years.

Arsia and Pavonis are two of the three Tharsis Montes volcanoes; what is the third?

Ascraeus is the tallest of the trio at over 18 km; the three line up north to south across the Tharsis bulge.

A scrap of which historic aircraft flew to Mars aboard the Perseverance helicopter?

The wing cloth is fastened under the helicopter's solar panel, and its first airstrip was dubbed Wright Brothers Field.

In which Martian valley did Mars Pathfinder land on 4 July 1997?

Mars Pathfinder bounced down on airbags in Ares Vallis, an ancient outflow channel chosen because floods should have washed a variety of rocks onto its plain.

NASA's 2001 Mars Odyssey orbiter was named as a tribute to which author?

Arthur C. Clarke, reached in Sri Lanka, said he would be delighted by the tribute to 2001: A Space Odyssey; the orbiter reached Mars in October 2001 and became the longest-serving spacecraft at another planet.

The HiRISE camera orbiting Mars can resolve surface features down to about what size?

HiRISE resolves features about 0.3 m (30 cm) across from roughly 300 km up; its half-metre mirror was the largest telescope sent to Mars.

How were certain meteorites first proven to come from Mars in 1983?

Glass in the EET79001 shergottite held gas resembling the air measured by the Viking landers; the family is known as SNC meteorites.

Which US president spoke in 1996 about possible fossils in a Mars meteorite?

Bill Clinton announced the ALH84001 findings from the White House lawn on 7 August 1996; the rock, found in Antarctica in 1984, fuelled astrobiology despite no convincing evidence of life.

After landing in 1997, the Mars Pathfinder lander was renamed after which scientist?

The lander became the Carl Sagan Memorial Station after Sagan's death in December 1996; it bounced down on airbags onto an ancient flood plain on 4 July 1997, a trick reused by the 2004 rovers.

Which 1976 lander experiment gave a positive result its lead scientist defended as life?

Gilbert Levin, lead scientist of Viking's Labeled Release experiment, maintained for decades that radioactive gas released after nutrients were added showed living microbes, though most of his peers concluded otherwise.

Which plain, the largest impact basin known, hosted Viking 2 and the Zhurong rover?

Utopia Planitia, about 3,300 km across, received Viking 2 in 1976 and China's Zhurong in 2021; in Star Trek the same plain hosts the Federation shipyards where the Enterprise-D and Voyager were built.

Which astronomer used Mars's orbit to discover that planets move in ellipses?

Astronomia nova (1609) drew on Tycho Brahe's precise naked-eye observations of the planet, gathered over many years.

What is the apparent backward drift of Mars against the stars near opposition called?

Retrograde motion occurs around opposition, when Earth overtakes Mars on its inside track and the red planet appears to loop backward against the stars for about two months.

In Roman myth, Mars fathered which legendary twins?

Romulus and Remus were the sons of Mars and the Vestal Rhea Silvia; the she-wolf that nursed the twins was Mars's sacred animal, alongside the woodpecker.

Which day of the week is named after Mars in French, Spanish and Italian?

Tuesday is mardi, martes and martedì, from Latin dies Martis; English instead honours the Germanic war god Tiw, giving 'Tiw's day'.

Which composer's orchestral suite opens with 'Mars, the Bringer of War'?

Gustav Holst wrote Mars first, in mid-1914, and despite its martial reputation finished it before the First World War began; The Planets premiered in 1918.

In biology, the astronomical symbol for Mars is used to denote what?

Carl Linnaeus set the convention in the 1750s, using Mars's shield-and-spear symbol for male and the hand mirror of Venus for female.

Of the other seven planets, which alone has a more eccentric orbit than Mars?

Only Mercury, with eccentricity about 0.21, beats Mars's 0.09; that eccentricity brings Mars closest to the Sun during southern summer, the season when global dust storms tend to start.

What colour does the sky around the setting Sun appear from the Martian surface?

Fine dust scatters light so the daytime sky looks butterscotch while sunsets glow blue, the reverse of Earth's.

Which feature, drawn by Huygens in 1659, was the first ever documented on another planet?

Syrtis Major, the dark wedge Huygens sketched in 1659, was called the Hourglass Sea by early mapmakers; its dark colour comes from dust-free basaltic volcanic rock.

Phoenix found about 0.5% of which life-unfriendly chemical in Martian soil in 2008?

Phoenix's wet chemistry lab measured perchlorate at roughly 0.5% of the soil; a 2017 study showed perchlorate salts become bactericidal under Martian-strength ultraviolet light.

Korolev crater's 2,200 km³ of ice matches the volume of which Canadian body of water?

Korolev's ice mound, up to 1.8 km thick, holds about 2,200 km³, roughly the volume of Canada's Great Bear Lake; the crater honours Sergei Korolev, chief designer of the Soviet space programme.

Russia's 2011 Fobos-Grunt mission, meant to sample a Martian moon, ended up where?

Fobos-Grunt's upper stage never fired, so it stayed stuck in low Earth orbit and re-entered in January 2012, taking with it Yinghuo-1, which would have been China's first Mars orbiter.

Which Curiosity instrument zaps rocks with a laser to read their composition?

ChemCam fires a laser at rocks up to about 7 m away and reads the spark's spectrum, a technique called laser-induced breakdown spectroscopy, to identify the elements present.

What powers the Curiosity rover on Mars?

Curiosity's radioisotope generator turns the heat of 4.8 kg of plutonium-238 dioxide into about 110 watts of electricity at launch, so dust storms never threaten it the way they did the solar-powered rovers.

What did Curiosity do on 6 August 2013 to mark one Earth year on Mars?

The rover has since found organic molecules such as benzene and propane in 3-billion-year-old rock samples.

What did Perseverance release a few days after landing, a first for any Mars mission?

Perseverance's microphone captured the first audio from Mars, a gust of wind released on 22 February 2021; its microphones later showed sound travels more slowly and faintly through the thin Martian air.

Perseverance's 2021 landing site was named after which science-fiction author?

NASA named the spot a few weeks after the 18 February touchdown, which came almost 15 years to the day after Butler's death.

Roughly how many public names flew to Mars on a chip aboard Perseverance?

NASA etched about 10.9 million (10,932,295) names onto three silicon chips on Perseverance's 'Send Your Name to Mars' plate; each registrant got a digital boarding pass listing launch and destination details.

Mars One, the Dutch venture selling one-way trips to Mars, met what fate in 2019?

It had hoped to fund a permanent colony partly through a reality-TV show, but no broadcast deal was ever struck.

Who co-wrote the 1990 'Mars Direct' plan and went on to found the Mars Society?

Robert Zubrin, with David Baker, proposed Mars Direct in 1990; its scheme makes the return propellant from Martian carbon dioxide and a small store of hydrogen carried from Earth, and Zubrin founded the Mars Society in 1998.

In which 1948 Bugs Bunny cartoon did Marvin the Martian make his debut?

Marvin first appeared in Haredevil Hare (1948), went unnamed in the original shorts and was only christened Marvin in 1979, once merchandising called for a name.

Which pulp author set his John Carter adventures on a Mars he called Barsoom?

Edgar Rice Burroughs's first Barsoom tale ran as Under the Moons of Mars in 1912 and was collected as A Princess of Mars in 1917.

Which word, coined as Martian in Heinlein's Stranger in a Strange Land, entered English?

Grok, Heinlein's Martian word for understanding something so fully it becomes part of you, entered English dictionaries; the novel won the 1962 Hugo Award for best novel.

Which late-1970s thriller follows a crewed Mars landing faked on a film set?

Capricorn One, directed by Peter Hyams, stars Elliott Gould as the reporter and James Brolin, Sam Waterston and O. J. Simpson as the astronauts whose Mars landing is staged on a soundstage.

Mars's diameter is roughly what fraction of Earth's?

Mars is about 6,800 km across, about half Earth's 12,700 km; its surface area is close to the area of Earth's dry land.

Which 1996 Tim Burton film, with Jack Nicholson in two roles including the US president, was based on a Topps trading-card series?

Mars Attacks! was Burton's 1996 send-up of 1950s invasion films, built on Topps's 1962 trading cards; its Martians' heads explode when they hear Slim Whitman's 'Indian Love Call'.

What is the term for the study and mapping of Mars's surface regions?

Areography, from the Greek name for Mars, parallels geography and selenography; Wilhelm Beer and Johann Mädler, better known for mapping the Moon, drew the first systematic chart of Mars in 1830–32.

Why did ESA's Schiaparelli lander crash on Mars in 2016?

A saturated inertial sensor made Schiaparelli's software believe it was below ground, so it released its parachute too early and fired its thrusters for only about three seconds; the Trace Gas Orbiter that carried it succeeded.

The Nozomi probe, which failed to reach Mars orbit in 2003, has a name meaning what?

Nozomi means 'hope' in Japanese; solar flares damaged its electronics en route, and a final attempt to orient it for orbit insertion failed in December 2003.