# How far away is Mars right now?

> Mars's distance from Earth, live, and why it swings so far. The signal delay, a day and a year on Mars, the cold, and the robots at work there.

HTML: https://www.theuniversecounts.com/solar-system/planets/mars

Numbers as of 2026-10-31 03:42 UTC. Live ones keep changing on the HTML page.

Right now Mars is about 215 million kilometres from Earth, and the gap changes every second. A radio message, moving at the speed of light, needs 12 minutes to cross it.

The distance swings a long way, because Earth and Mars circle the Sun at different speeds. At their closest the two planets come within 54.6 million kilometres. At their farthest they are 401 million kilometres apart. The next close approach is on 20 February 2027.

- Time until Mars's next close approach to Earth: 111 d 20 h 30 m 58 s
- Length of a solar day on Mars (a sol): 24 h 39 m 34 s
- Average surface temperature of Mars: -59 °C
- Number of known moons of Mars: 2

## A small red world

What is Mars?

Mars is the fourth planet from the Sun, the next world out after Earth. Like Earth, it is made of rock and metal, with solid ground you could stand on.

It is smaller than our world. Earth is about 1.9 times as wide, and about 6.6 planets the size of Mars would fit inside it. Yet Mars is still about 2 times as wide as our Moon.

Its colour gave it its name. Iron minerals in the Martian dirt have rusted, so the ground looks red. Dust in the air turns the sky a hazy red too. The Romans named the planet after their god of war, because it reminded them of blood. The Egyptians called it "Her Desher", the red one.

Today Mars is a cold, dusty desert under a very thin sky. But the rocks tell us it was once wetter and warmer, with a thicker atmosphere, billions of years ago.

## Why the distance keeps changing

The next close approach

Earth and Mars both circle the Sun, like two runners on a track. Earth has the inside lane and the faster pace. It goes round once a year, while Mars needs about 1.9 Earth years.

So every so often Earth catches up with Mars and overtakes it. Then the two planets are on the same side of the Sun, and as close as they get. Afterwards Earth pulls ahead, until Mars lies on the far side of the Sun from us. On average, Earth laps Mars about once every 2.1 years.

At the far point, Mars can be 401 million kilometres away. At the best close approaches the gap shrinks to 54.6 million.

Not every meeting is equally close. Mars's orbit is more oval than Earth's, so it matters where on that oval Earth catches up. Near the far end, the two stay well apart even at their closest. The clock on this page counts down to the next meeting, on 20 February 2027.

## A hello that takes minutes

Right now

Radio waves are a kind of light, and nothing travels faster. Even so, a message to Mars is never instant. At today's distance a command needs 12 minutes to arrive, and the reply needs as long again.

That delay shapes how we work there. No one can steer a rover on Mars with a joystick. By the time a picture of a rock reaches Earth, the moment it shows is already minutes old.

So the teams plan ahead. Each day they send a rover its instructions, timed for the moment it wakes and turns its antenna towards Earth to listen. Then it works through the list on its own.

About every two years the Sun passes between the two planets. Hot gas from the Sun could garble the signals, so for about two weeks the teams send no new commands. The robots on Mars carry on with simpler plans until the line is clear.

## A day and a year

One sol

A day on Mars feels familiar. Mars spins at almost the same pace as Earth, so from one sunrise to the next takes 24 h 39 m 34 s. Mission teams call a Martian day a sol, short for solar day.

The year is another matter. Mars lies farther from the Sun and moves more slowly along a longer path. One lap takes about 1.9 Earth years, or about 669 sols. Someone born on Mars would wait almost two Earth years for each birthday.

Mars is tilted on its axis, as Earth is, so it has seasons. Because its year is long, its seasons are long too. And because its orbit is oval, they are uneven: on Mars, northern spring is the longest season of all, and northern autumn the shortest.

## The cold

Average temperature

Mars is farther from the Sun than we are, so its sunlight is weaker. Its air is thin, mostly carbon dioxide, and it holds very little warmth. So the heat of the day escapes easily into space.

Averaged over the whole planet, the surface temperature on Mars is -59 °C. Earth's average is 15 °C. Both are averages, but they show the gap: Mars sits far below freezing, Earth above it. The thin air also lets the ground cool fast after sunset, so one place can swing widely between day and night.

The cold is not the same everywhere. Near the equator at noon in summer, the ground can be mild. NASA says that if you stood there, it would feel like spring at your feet and winter at your head. At the poles in winter it is far colder still.

## The robots working there now

As of October 2026

NASA calls Mars the only planet we know of that is inhabited entirely by robots. It is also the only planet where we have sent rovers to roam.

Two of them are working there now, both NASA's. Curiosity landed in Gale Crater on 6 August 2012, and is now climbing the slopes of Mount Sharp. Perseverance landed in Jezero Crater on 18 February 2021. The crater once held a lake, fed by rivers. The rover looks for signs of ancient life and collects cores of rock and soil.

Above them, orbiters relay their data home. NASA's Mars Reconnaissance Orbiter and Mars Odyssey share the work with Europe's Mars Express and Trace Gas Orbiter. Odyssey has circled Mars since 24 October 2001.

Not every robot lasts. NASA's MAVEN orbiter fell silent on 6 December 2025, and NASA declared its mission over on 3 June 2026. Each picture the others send crosses the gap at the speed of light, and arrives a few minutes late.

## FAQ

### How far away is Mars right now?

About 215 million kilometres, measured from the centre of Earth to the centre of Mars. The number on this page is live. Over about two years it swings between 54.6 million and 401 million kilometres.

### When is Mars closest to Earth next?

On 20 February 2027. Around the same time Mars is at opposition: opposite the Sun in our sky, rising at sunset and up all night. Each meeting is a little different, because Mars's orbit is oval. The best ones bring it within 54.6 million kilometres.

### Will Mars ever look as big as the full Moon?

No. The claim comes from a chain email that has gone round since 2003. The original said Mars would look as large as the full Moon only through a telescope that magnified it many times. To the naked eye, even at its record approach in August 2003, Mars looked like a bright star.

### How many moons does Mars have?

2: Phobos and Deimos. Asaph Hall discovered both in August 1877. They are small and potato-shaped, and may be captured asteroids. Phobos, the larger one, is slowly moving closer to Mars.

### How long does it take Mars to orbit the Sun?

A year on Mars, one trip round the Sun, lasts about 1.9 Earth years. It holds about 669 sols, so someone born on Mars would wait almost two Earth years for each birthday.

### How long is a day on Mars?

24 h 39 m 34 s from one sunrise to the next, a little longer than a day on Earth. Mission teams call it a sol.

## Related

- [Planets](https://www.theuniversecounts.com/solar-system/planets.md)
- [The Sun](https://www.theuniversecounts.com/solar-system/the-sun.md)
- [Spacecraft](https://www.theuniversecounts.com/solar-system/spacecraft.md)
- [Venus](https://www.theuniversecounts.com/solar-system/planets/venus.md)

Somewhere under that small red light in the night sky, two rovers are at work. What would you ask them to look for next?

## Sources

- Average surface temperature of Earth (Measured, with error): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html)
- Average surface temperature of Mars (Measured, with error): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Average time between Mars's close approaches to Earth (synodic period) (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Earth's average distance from the Sun in kilometres (Measured): [NASA: Earth: Facts](https://science.nasa.gov/earth/facts/)
- Earth's diameter at the equator (Measured): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html)
- Equatorial diameter of Mars (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Largest possible distance between Earth and Mars (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Length of a solar day on Mars (a sol) (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html); [NASA Science: Mars Facts](https://science.nasa.gov/mars/facts/)
- Length of a year on Earth (Measured): [NASA NSSDCA: Earth Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html)
- Length of a year on Mars (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Mars's distance from Earth (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Number of known moons of Mars (Measured): [NASA: Moons: Facts](https://science.nasa.gov/solar-system/moons/facts/)
- Smallest possible distance between Earth and Mars (Measured): [NASA NSSDCA: Mars Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html)
- Speed of light in a vacuum (Measured): [BIPM: SI defining constants](https://www.bipm.org/en/measurement-units/si-defining-constants)
- The Moon's mean diameter (Measured): [NASA NSSDCA: Moon Fact Sheet](https://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html)
- Time until Mars's next close approach to Earth (Measured): [National Astronomical Observatory of Japan (NAOJ): 火星が地球に最接近（2027年2月）](https://www.nao.ac.jp/astro/sky/2027/02-topics05.html); [SEDS (Students for the Exploration and Development of Space): Mars 2027](https://spider.seds.org/spider/Mars/mars2027.html)
- Typical cruising speed of a long-haul airliner (Estimated): [EUROCONTROL: Aircraft Performance Database: B789 (Boeing 787-9)](https://contentzone.eurocontrol.int/aircraftperformance/details.aspx?ICAO=B789); [EUROCONTROL: Aircraft Performance Database: A388 (Airbus A380-800)](https://contentzone.eurocontrol.int/aircraftperformance/details.aspx?ICAO=A388)