Fun Facts About Mars: The Planet Run Entirely by Robots

A 28-year-old woman refused to stop at the “pretty red planet” version of Mars, and honestly, she should be in charge of every Mars documentary from now on. Because the second you peel back the rust-colored dust, the whole place turns into a world that looks familiar, then immediately refuses to act normal.

It gets complicated fast, too, because Mars is running the show without human hands. NASA rovers are out there snapping pictures of blue sunsets, while dust storms can grow so huge they effectively turn the planet into a weeks-long blackout. And just when you think you’ve got the vibe, Mars throws carbon dioxide snow into the forecast.

By the time you’re done with these fun facts, you’ll start wondering if Mars is the planet, or the prank.

Why Mars Is Red, and What It's Actually Like

The color is rust. Literally. According to NASA, Mars looks red because the iron in its soil and dust has oxidized, the same chemical process that rusts a nail. Up close the surface is browner and more golden than the postcard red suggests.

The Romans named it for their god of war, since the bloody color reminded them of battle. They borrowed the idea from the Greeks and their war god Ares. The Egyptians called it "Her Desher," the red one. Ancient Chinese astronomers called it the fire star. Everyone, independently, looked up and saw the same angry red dot.

A few quick Mars facts:

• A day on Mars runs just 37 minutes longer than a day on Earth.
• Mars has two small, lumpy moons, Phobos and Deimos, both likely captured asteroids.
• Despite being half Earth's diameter, Mars has roughly the same amount of dry land, since Earth is mostly ocean.

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The rust is only the opening act, because Mars looks red for the same reason a nail does, oxidized iron dust that turns the whole surface into a giant weathered postcard.

Mars Facts About Its Record-Breaking Landscape

Mars holds the biggest terrain in the solar system, at both extremes. Olympus Mons is the largest volcano known anywhere, standing about three times the height of Mount Everest and spreading as wide as the state of Arizona.

It's so broad and so gently sloped that, standing on it, the summit would curve away out of sight. You wouldn't even register it as a mountain.

Then there's Valles Marineris, a canyon system long enough to reach from California to New York. It runs about 2,400 miles, dwarfing the Grand Canyon, and in places drops more than five miles deep. The same planet holds the solar system's tallest volcano and its longest canyon.

Things About Mars That Sound Invented

Mars has weather, and it's stranger than Earth's:

1. Sunsets on Mars are blue. The fine dust scatters light in a way that flips our color logic, so the sky reddens by day and turns blue at dusk. NASA's Curiosity rover has photographed those eerie blue Martian sunsets.
2. Mars gets dust storms so vast they can swallow the entire planet for weeks.
3. It snows carbon dioxide. Temperatures drop low enough that CO2 freezes straight out of the air as dry-ice frost.

The planet also shakes. As the Smithsonian's National Air and Space Museum reports, NASA's InSight lander recorded more than 1,300 marsquakes, proving Mars is still geologically restless beneath the surface.

Even its moons hint at a violent past, since Phobos and Deimos look so much like the asteroids photographed drifting through the solar system that many scientists think Mars simply caught them with its gravity, leftovers from the same family of asteroids like the one that ended the dinosaurs.

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But once you zoom out from the color, the timeline gets weird, since a day on Mars runs just 37 minutes longer, and even the clocks can’t keep up.

And if you love extreme geography, Chile’s 2,600-mile length, 100-mile width, and the driest desert will blow your mind.

Then the landscape goes full flex, with Olympus Mons so massive it would basically disappear from view at the top, and Valles Marineris stretching from California to New York in canyon form.

Mars Facts About Exploration

Mars is the most explored planet beyond Earth. More than a dozen spacecraft have reached it, and several rovers are still working on the surface today. NASA's Perseverance rover is collecting rock samples right now for a future mission to haul them back to Earth.

It also carried Ingenuity, a small helicopter that became the first aircraft ever to fly on another planet, logging more than 70 flights in air a hundred times thinner than ours. For all its hostility, Mars is the one other world humans seriously plan to walk on, with crewed missions targeted for sometime in the 2030s.

Mars Facts About Its Moons and Thin Air

Mars has two small moons, Phobos and Deimos, and they're nothing like ours. Both are lumpy, potato-shaped rocks just a few miles across, almost certainly captured asteroids. Phobos orbits so close and so fast that it laps the planet three times a day, rising in the west and setting in the east. It's also creeping inward, and in tens of millions of years it will likely be torn apart by Mars's gravity, possibly forming a faint ring.

The air on Mars is barely there. The atmosphere is about 100 times thinner than Earth's and almost entirely carbon dioxide, which is why liquid water can't survive on the surface today. It would boil away or freeze almost instantly.

A few more Mars facts that change the picture:

• Gravity on Mars is only about 38 percent of Earth's. A person who weighs 100 pounds here would weigh under 40 there.
• Mars has planet-wide dust storms. Every few years, swirling dust can wrap the entire globe and block out the sun for weeks.
• A year on Mars lasts 687 Earth days, nearly twice as long as ours, because it sits farther from the Sun. A single Martian day, called a sol, runs about 24 hours and 37 minutes, eerily close to our own. Temperatures swing brutally across it, from around 20°C on a warm afternoon near the equator to below -120°C at the frozen poles, since the thin air holds almost no heat.

The thin air is a clue to what went wrong. Mars once had a thicker atmosphere, rivers, and lakes. But it lost its global magnetic field billions of years ago, and without that shield the solar wind slowly stripped the atmosphere away. The cold desert we see today is what's left of a world that may once have looked a lot more like Earth. Spacecraft keep sending back the proof, from a NASA rover roaming Mars to orbiter images that look almost unreal.

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Finally, the sky starts acting like it’s breaking rules, because Curiosity has photographed blue sunsets and dust storms that can swallow the entire planet for weeks.

Why Mars Still Pulls Us In

For all its hostility, dry, freezing, and bathed in radiation, Mars is the planet we keep reaching toward. Billions of years ago it was warmer and wetter, with rivers, lakes, and a thicker atmosphere. Dried-up riverbeds and ancient shorelines are still visible from orbit today.

That lost water is the whole reason we keep sending rovers. If life ever started on Mars, the evidence is likely buried in those old lakebeds, and finding it would reshape how we see Earth, the one planet we know that's still alive.

So the real fun fact about Mars is that it works as a preview and a warning at once. It shows what a wet, living world can become when it loses its air and water. The robots are there to read that story before we ever arrive in person.

More space reads on Postize: fun facts about Jupiter and fun facts about the planets.

Mars is red, huge, and dramatic, but the real twist is that it’s mostly being filmed by robots while it does all the weird stuff anyway.

For more space curveballs like the planet that got demoted, see this quick tour of all eight planets, plus the demoted one.