96 Fun Facts About Mars

What gives Mars its distinctive reddish appearance?

Iron oxide (rust) on its surface tints the fine dust that blankets Mars, and winds lift so much of it that even the daytime sky looks hazy and butterscotch-coloured.

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

Olympus Mons stands more than twice the height of Everest; a big reason is that Mars has no drifting plates, so lava kept piling up over a single hotspot.

What do mission teams call a Martian day, which runs about 40 minutes longer than a day on Earth?

A sol lasts 24 hours 39 minutes 35 seconds, so teams working on Mars time start their shifts about 40 minutes later each Earth day and slowly drift around the clock.

Which canyon system on Mars is long enough to stretch from California to New York?

Valles Marineris runs roughly 4,000 km and is thought to have begun as a giant crack in the crust, pulled open as the neighbouring Tharsis volcanic region swelled.

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

About 0.6% of Earth's sea-level pressure is all the thin Martian air manages, close to the triple point of water, so liquid water on the surface would boil away 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 NASA lander recorded more than 1,300 marsquakes between 2018 and 2022?

InSight placed its seismometer directly on the ground, and the tremors it recorded showed that Mars is still active inside; dust smothering its solar panels finally ended the mission in December 2022.

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

About 38% of Earth's pull means someone who weighs 100 kg here would register about 38 kg on Mars; the weak gravity is also one reason Martian volcanoes could grow so tall.

What is the primary component of Mars's atmosphere?

Carbon dioxide makes up about 95% of Mars's atmosphere, with a few percent of nitrogen and argon and only traces of oxygen, which is why NASA has tested a device that splits the gas to make breathable oxygen.

What kind of feature is Hellas Planitia, whose floor holds the lowest point on Mars?

An impact basin about 2,300 km wide, Hellas is so deep that winter air pressure on its floor is about twice the Martian average, enough in principle for liquid water to exist there.

Which NASA rover landed in 2004 for a 90-day mission and kept working for more than 14 years?

Opportunity drove more than 45 km before a planet-wide dust storm blotted out its solar panels in June 2018; NASA ended the mission in February 2019 after over a thousand recovery commands went unanswered.

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?

Gale Crater surrounds Mount Sharp, a mountain about 5.5 km high that Curiosity has been climbing for more than a decade; several lines of evidence show the crater once held a lake.

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

Viking 1 was meant to land on 4 July 1976, the US bicentennial, but orbital photos showed the chosen site was too rough, so touchdown slipped to 20 July, seven years to the day after Apollo 11's Moon landing.

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

Sojourner was named for the abolitionist Sojourner Truth by a 12-year-old who won an essay contest; built to last about a week, the rover kept exploring for nearly three months.

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 showed that breathable oxygen can be pulled straight out of the thin Martian air, about 122 grams of it in all, a first 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?

MAVEN was the first mission devoted to Mars's upper atmosphere; by measuring how fast gas escapes, it showed that the solar wind stripped away most of the planet's early air and left the cold desert seen today.

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

Spirit and Opportunity landed on opposite sides of Mars in January 2004; each carried metal from the fallen World Trade Center, shaped into shields for the cables of its rock drill.

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

Water ice gave itself away when dice-sized bright lumps in a trench dug by Phoenix's robotic arm vanished over four days, turning straight from solid to vapour in the thin air.

What did the Curiosity rover photograph in 2012 that showed a stream had once flowed across its landing site?

Rounded pebbles cemented into rock were too big for wind to have carried, so water must have tumbled them smooth; the team judged the stream had been between ankle and hip deep.

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 single giant impact early in Mars's history blasted out the northern lowlands.

What is the average surface temperature on Mars?

About -63°C (-81°F) is the commonly quoted average, but the thin air holds so little heat that readings range from about 20°C at the equator at midday down to about -153°C at the poles.

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

Dry ice (frozen CO2) covers the southern cap all year, whereas in the north it vanishes each summer to expose frozen water; beneath the southern dry ice lies a much thicker layer of frozen water too.

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

About 687 days, nearly two Earth years, because Mars circles farther out and moves more slowly; each of its seasons lasts roughly twice as long as ours.

Each spring, jets of gas bursting through Mars's south polar ice carve dark, branching channels nicknamed what?

Spiders form when spring sunlight warms the ground beneath the seasonal ice: trapped gas builds up, bursts through the slab and scours channels that radiate from each vent, a process seen nowhere on Earth.

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

Nergal was the Mesopotamian god of war, plague and death, so the blood-red planet was tied to bloodshed long before the Romans named it for their own war god.

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

Fear and Dread are what Phobos and Deimos mean; in Greek myth the pair are usually the sons of the war god and go into battle at his side.

Who discovered Mars's two moons in 1877?

Asaph Hall was ready to abandon the hunt until his wife, Angeline Stickney, urged him on; he found both moons within a week in August 1877, and the largest crater on Phobos is now called Stickney.

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

Percival Lowell took Schiaparelli's 'canali', Italian for channels, to be canals dug by an intelligent civilization; the observatory he founded to study them later discovered Pluto.

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 did sharper photographs reveal the 1976 'Face on Mars' to be?

A mesa in the Cydonia region looked like a face in a low-resolution orbiter photo because of the angle of the light and shadow; a far sharper image taken in 2001 showed an ordinary eroded hill.

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

The War of the Worlds became notorious in 1938, when Orson Welles's radio version, staged as news bulletins, convinced some listeners that an invasion was under way; newspapers greatly exaggerated the panic.

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

Potatoes in soil fertilized with human waste keep Watney alive in a story Andy Weir first posted free on his website, a chapter at a time, before a 99-cent Kindle edition became a bestseller.

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

Ray Bradbury had already sold most of the stories to magazines when a Doubleday editor suggested stitching them into one book, which became The Martian Chronicles in 1950.

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

Turbinium mining is why the film's Mars is colonized, under the tyrant Vilos Cohaagen; Arnold Schwarzenegger himself persuaded the studio Carolco to buy the long-stalled script so that he could star.

Which singer's 1971 album Hunky Dory includes the song 'Life on Mars?'?

David Bowie wrote it as a parody of Frank Sinatra's 'My Way', a song whose French original he had earlier tried, and failed, to turn into an English-language hit.

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

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

Roughly how long does a one-way trip to Mars take on the most fuel-efficient route?

About 9 months each way on the minimum-energy path, and a crew would then have to wait more than a year on Mars for the planets to line up again, so a round trip takes close to three years.

Roughly how often does a good launch window from Earth to Mars open?

About every 26 months Earth and Mars line up for a low-energy crossing, which is why missions leave in clusters: in July 2020 the UAE, China and the United States all launched within two weeks.

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

Engineering an Earth-like environment would mean thickening and warming Mars's air until people could live outside without spacesuits; a 2018 NASA-backed study concluded it cannot be done with present-day technology.

Which planet-wide shield, lost by Mars about four billion years ago, helps protect Earth from cosmic radiation?

A magnetic field steers charged particles away from Earth; Mars has none, and a detector riding to Mars with the Curiosity rover found that the radiation on a round trip would pose a serious health risk to a crew.

A radio command sent from Earth takes roughly how long to reach a rover on Mars?

Minutes: anywhere from a few to more than twenty, depending on where the two planets are, so nobody steers a rover live; teams upload a batch of instructions and the machine carries them out alone.

Which gas detected by the Curiosity rover intrigues scientists because living things make most of Earth's supply?

Methane is destroyed by sunlight within a few centuries, so any found today must have been released recently, by microbes or by rock reacting with water; yet a European orbiter built to sniff for it has found none.

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

Fourth planet from the Sun, Mars orbits about one and a half times as far out as Earth, at an average of 228 million km, so it receives less than half as much sunlight.

What type of planet is Mars classified as?

Terrestrial (rocky) worlds formed close to the young Sun, where only rock and metal could withstand the heat while ices gathered farther out, which is why the gas and ice giants all orbit beyond them.

Which mineral makes up the tiny 'blueberries' that a NASA rover found scattered across Meridiani Planum?

Hematite had been spotted from orbit, which is why NASA sent a rover to that plain; the millimetre-sized 'blueberries' it found turned out to be concretions that grew inside water-soaked rock.

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

India reached Mars orbit in September 2014 at its first attempt; the mission had been approved only 15 months before launch and kept costs down by reusing the design of the country's first Moon probe.

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.

A hoax email first sent in 2003 and revived many times since claims Mars will look as big as what?

The full Moon comparison grew out of a real event: in August 2003 Mars came closer to Earth than it had in nearly 60,000 years, yet to the naked eye it was still only a bright dot.

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?

Japan's Tanegashima Space Center launched the UAE's orbiter on a Mitsubishi H-IIA rocket in July 2020, timed so that it reached Mars in 2021, the year of the country's fiftieth anniversary.

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

Mixed metric and imperial units doomed it: ground software reported thruster impulse in pound-force seconds while the navigation software expected newton-seconds, so the orbiter came in far lower than planned and was lost.

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

Blur's call sign never played: Beagle 2 fell silent on arrival in December 2003, and orbital photos in 2015 showed it had landed safely but with solar panels blocking its radio antenna.

Which ESA orbiter's radar detected signs of a possible lake of liquid water beneath Mars'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.

Because Phobos orbits Mars faster than the planet spins, where does it rise for an observer on the surface?

In the west: Phobos laps Mars in just 7 hours 39 minutes, so it overtakes the turning ground, crosses the sky in about four hours and sets in the east, usually twice in a single Martian day.

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

Break up into a ring is one forecast for Phobos: tides are dragging it about 1.8 metres closer to Mars every century, and within roughly 50 million years the planet's gravity should tear it apart.

Mars has four seasons like Earth because the two planets share which feature?

A tilted axis of about 25 degrees, close to Earth's 23.4, gives Mars its seasons, and its polar caps grow and shrink with them, a change astronomers could already watch through telescopes two centuries ago.

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

The 1903 Wright Flyer gave up a small swatch of its wing fabric, fixed beneath the helicopter's solar panel; NASA then named the site of that first takeoff Wright Brothers Field.

Which landing system set the one-tonne Curiosity rover down on its wheels in 2012?

Sky crane: a rocket-powered stage hovered above the surface and lowered the rover on nylon tethers, because Curiosity was too heavy for the airbags that had cushioned earlier, smaller rovers.

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 pick out objects as small as what?

A dinner table is about the smallest thing HiRISE can pick out from orbit, sharp enough for NASA to check landing sites for large rocks that could wreck a lander before a mission touches down.

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

Trapped gas matched the planet's air: gas sealed inside glass in one of the meteorites closely resembled the Martian atmosphere the Viking landers had sampled, direct evidence that the rock was blasted off Mars.

Which US president made a televised statement about possible fossils in a meteorite from Mars?

Bill Clinton spoke after NASA scientists reported possible microfossils in a rock found in Antarctica in 1984; footage of his statement was later reused in the film Contact.

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 hidden message was coded into the pattern of Perseverance's landing parachute?

Dare Mighty Things was hidden in binary code by NASA engineer Ian Clark in the parachute's coloured panels, and puzzle fans on Twitter deciphered it soon after the landing video appeared.

Which Martian plain was the landing site of both NASA's Viking 2 and China's Zhurong rover?

Utopia Planitia was a second choice for Viking 2, whose original site looked too rough from orbit; in Star Trek the plain hosts the shipyards that built the Enterprise-D and Voyager.

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

Johannes Kepler spent years fitting Tycho Brahe's naked-eye measurements of Mars to circles and ovals before he accepted an ellipse, the result he published in Astronomia nova in 1609.

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

Retrograde motion happens around opposition, when Earth overtakes Mars on its inside track and the red planet seems to loop backward against the stars before resuming its usual drift.

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?

Male: Carl Linnaeus began marking the sexes of plants with planet signs in the 1750s, and Mars's circle and arrow, traditionally read as the war god's shield and spear, has stood for male ever since.

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

Only Mercury, at about 0.21, beats Mars's 0.09; the lopsided orbit makes Martian seasons unequal, with northern spring lasting 194 Martian days and northern autumn only 142.

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 astronomer, discoverer of Saturn's moon Titan, sketched the first recognisable feature on Mars in 1659?

Christiaan Huygens drew the dark wedge now called Syrtis Major and, by timing its return night after night, worked out that a Martian day lasts roughly as long as one on Earth.

Which toxic chemical, also an ingredient of solid rocket fuel, did the Phoenix lander find in Martian soil in 2008?

Perchlorate turned up in Phoenix's on-board chemistry lab, a surprise with a sting: a 2017 study found that under Mars-like ultraviolet light the salts become deadly to bacteria.

Which Soviet chief designer, who led the Sputnik and Gagarin flights, has an ice-filled Martian crater named after him?

Sergei Korolev's identity was a state secret until he died in 1966, so the public never heard his name while his rockets made headlines; the crater named for him holds a mound of ice 1.8 km thick all year.

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

Stuck in low Earth orbit after the engine burns meant to send it to Mars failed, Fobos-Grunt fell back 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's laser vaporises a pinhead-sized speck of rock, and a spectrograph reads the light of the glowing plasma to name the elements inside, so the rover can test a target from a distance without touching it.

What powers the Curiosity rover on Mars?

A plutonium-238 generator turns the heat of 4.8 kg of the decaying fuel into electricity, so dust storms never threaten Curiosity the way they did the solar-powered rovers.

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

Played 'Happy Birthday' to itself, alone on Mars; the rover has kept working for more than a decade since, finding organic molecules in 3-billion-year-old rock along the way.

Which first for a Mars rover did Perseverance send home within days of its 2021 landing?

Audio of Martian wind was the first sound a microphone ever recorded on Mars; later recordings showed that sound there travels more slowly and comes across far quieter than on Earth.

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

Octavia E. Butler was born in Pasadena, California, home of the laboratory that built and drives the rover, and its team named the touchdown spot for her about two weeks after the landing.

What did nearly 11 million people send to Mars aboard the Perseverance rover?

Their names, 10,932,295 of them, were etched by electron beam onto three fingernail-sized silicon chips, and everyone who signed up received a souvenir boarding pass.

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

Bankruptcy was declared in a Swiss court in January 2019; the venture had hoped to pay for a permanent colony largely through a reality-TV show about its crews, but no deal with producers was ever reached.

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

Robert Zubrin and David Baker built Mars Direct around one money-saving trick: make the fuel for the trip home on Mars itself, from its air and a little hydrogen brought from Earth; Zubrin founded the Mars Society in 1998.

Why does Looney Tunes' Marvin the Martian want to blow up the Earth?

It blocks his view of Venus, he tells Bugs Bunny; the character went unnamed through all five of his original cartoons, from Haredevil Hare in 1948 on, and only became 'Marvin' in 1979.

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

Edgar Rice Burroughs signed his first Barsoom serial 'Normal Bean' in 1912 to show he was still sane despite the wild story, but a typesetter printed it as 'Norman Bean'; it later became the novel A Princess of Mars.

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

Grok literally means 'to drink' in the novel's Martian language; readers in the 1960s counterculture took it up for deep, intuitive understanding, and it later became everyday programmers' slang.

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

Capricorn One casts NASA as the villain, yet the agency lent the production real hardware, including a prototype lunar module; O. J. Simpson, James Brolin and Sam Waterston play the astronauts.

Mars's whole surface roughly matches the area of what on Earth?

All its dry land: Mars is only about half as wide as Earth, but with no oceans its whole surface is ground, and that comes to nearly the area of Earth's continents and islands combined.

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 took shape when Wilhelm Beer and Johann Mädler, better known for mapping the Moon, charted Mars and chose a small dark spot as zero longitude; the planet's prime meridian still runs through it.

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

Its parachute released too early because a saturated motion sensor made the software believe the lander was already below ground; the thrusters then fired for only about three seconds instead of thirty.

What did SpaceX launch toward the orbit of Mars on the first Falcon Heavy flight in 2018?

A Tesla Roadster, Elon Musk's own car, stood in for a payload with a spacesuited mannequin called Starman in the driver's seat; it now loops around the Sun on a path that crosses the orbit of Mars.