Learn · questions about Mars
Learn about Mars
Plain answers to the questions people ask about Mars, each with the number first and the sources at the end. Pick a question, try a live tool, or look up a word in the glossary.
Updated Sources (1)
Big questions
Each answer starts with the number, then explains it.
- Can humans live on Mars?Thin air, radiation, cold and dust make Mars deadly without protection. What a Mars base would need — air, water, food, shelter — and how close we are.
- How long does it take to get to Mars?About seven months: 22 missions took 131 to 333 days to reach Mars, and half took 209 days or fewer. Why it varies, every trip in a table, and crewed trips.
- Is there a live feed from Mars?There is no live video from Mars — here is why, and the closest thing: the rovers’ newest raw images, posted hours to days after they’re taken.
- When will humans land on Mars?No crewed Mars mission is funded or scheduled yet. What NASA, SpaceX and China plan, what still has to be solved, and the earliest realistic dates.
- When will SpaceX go to Mars?SpaceX put the Moon first in 2026; Musk says a Mars city could begin in 5 to 7 years. What its Mars plan is, what Starship still needs, and the timeline.
Live tools
Worked out in your browser from NASA data, to the second where the data allows.
- How far is Mars from Earth right now?Live Earth–Mars distance in km and miles, updated every second, with the signal delay and the closest and farthest Mars gets.
- Mars launch calendarEvery upcoming Mars launch, landing, arrival and sky event, with live countdowns — and dates only as precise as the sources allow.
- Mars launch windowsMissions to Mars leave every 26 months, when Earth and Mars line up. How Hohmann transfers work, live planet positions, and when the next window opens.
- Mars photosThe newest real photos from Mars, pulled daily from NASA's Perseverance and Curiosity rovers, with each picture's camera, date and credit.
- Mars roversTwo rovers are working on Mars right now: Perseverance and Curiosity. See all six rovers that have driven on Mars, where they landed and what happened to each.
- What time is it on Mars?The time on Mars right now, local time at the rovers, today's sol and the Martian season — live, calculated with NASA's Mars24 method.
- Where is Mars tonight?Find Mars in tonight's sky from where you are, and know when it's brightest: Mars reaches opposition on Feb 19, 2027, its best view until 2029.
Mars facts and features
The planet itself: size, gravity, weather, moons, water and more.
- Deimos: Mars’s small outer moonDeimos is the smaller of Mars’s two moons — about 12 km across, orbiting every 30 hours. Facts, images and theories about where it came from.
- Hellas PlanitiaHellas is one of the largest impact basins in the solar system and the lowest place on Mars: more than 2,000 km across and up to 9 km deep. Facts and images.
- How far is Mars from the Sun?Mars orbits between about 207 and 249 million km from the Sun (1.38–1.67 AU). Its distance right now, and how its orbit shapes seasons and dust storms.
- How long is a day on Mars?A day on Mars (a sol) lasts 24 hours, 39 minutes and 35 seconds. A Mars year is 687 Earth days. How Martian days, seasons and calendars work.
- How many moons does Mars have?Mars has two small moons, Phobos and Deimos. How big they are, how they move, where they may have come from, and the mission going to find out.
- How strong is gravity on Mars?Gravity on Mars is 38% of Earth's — 3.73 m/s². Use the calculator to see what you'd weigh on Mars and what low gravity means for astronauts.
- Is there life on Mars?No life has been confirmed on Mars. What rovers have found, including a rock NASA called a potential biosignature in 2025, and what would prove it.
- Mars exploration timelineEvery mission to Mars since 1960 — flybys, orbiters, landers and rovers — with what each found and which ones failed.
- Mars factsKey facts about Mars — size, gravity, temperature, day length, moons, distance — plus fun facts, all sourced, with live numbers for where Mars is right now.
- Mars glossaryPlain-English definitions of the words you meet on Mars pages, from sol and Ls to launch window and opposition, each with a live example.
- Mars mapAn interactive map of Mars with every successful landing site, the biggest volcanoes and canyons, and the half of the planet in night right now.
- Mars vs EarthMars is about half Earth’s width with 38% of its gravity, a day about 40 minutes longer and a 687-day year. A side-by-side comparison of the two planets.
- Mars weatherMars averages about −65 °C (−85 °F), NASA says, and ranges from about 20 °C to −153 °C. The latest reading from Curiosity, the season now and dust storms.
- Olympus MonsOlympus Mons rises about 22 km — roughly two and a half times Everest — and covers an area about the size of Arizona. How it formed and how it compares.
- Phobos: Mars’s larger moonPhobos is Mars' larger moon — about 22 km across, circling Mars three times a day and slowly spiraling in. Facts, rover-seen eclipses and Japan's MMX mission.
- The atmosphere of MarsMars’s air is 95% carbon dioxide, at less than 1% of Earth’s surface pressure. What it’s made of, why Mars lost most of it, and whether you could breathe it.
- The surface of MarsRed dust, giant volcanoes, deep canyons and polar ice: a tour of the Martian surface, its soil, rocks, craters and dunes, and where the big landmarks are.
- Valles MarinerisValles Marineris is about 3,870 km long, up to 600 km wide and 9.3 km deep. How Mars’s giant canyon formed and how it compares to the Grand Canyon.
- Water on MarsMars has lots of water — frozen in its polar caps and underground. Liquid water flowed there billions of years ago. Where it is today and where the rest went.
- Why is Mars red?Mars is red because its dust is rich in iron oxide — rust. Recent research suggests that rust formed when Mars was wetter. The science, simply.
Words to know
17 Mars words, from SolA sol is a day on Mars — 24 h 39 min 35 s, about 40 minutes longer than ours — and rovers count them from the day they land.More in the glossary to OppositionOpposition is when Earth passes between the Sun and Mars, so Mars rises at sunset, stays up all night and looks its brightest — about every 26 months.More in the glossary, each in one sentence.
The Mars glossarySources
- Mars Progress — Sources and methodsPrimary · checked Oct 4, 2026