Terrestrial Planet

Mars.

A cold desert world with the tallest volcano in the solar system and the ghosts of ancient rivers.

Mars right now

From Earth right now: 242,053,055 km
Its light reaches us after: 13 min 27.4 s
From the Sun: 234,334,103 km
Speed around the Sun: 23.46 km/s
Around its orbit: 28% of the way from perihelion

Worked out in your browser from JPL's orbital elements, the same maths that moves the planets in the 3D viewer. How far Mars is from Earth right now, with miles, AU and the next close approach.

Overview

Mars at a glance

Mars is the fourth planet from the Sun, the Red Planet, with a thin CO₂ atmosphere and an iron-oxide-rich surface that gives it its colour. Its diameter of 6,779 km is roughly half Earth's. A Martian day (24h 37m) is almost the same as Earth's, but a year takes 687 Earth days. Mars hosts Olympus Mons, the tallest volcano in the solar system at 22 km, and Valles Marineris, a canyon system 4,000 km long.

Diameter: 6,779 km
From the Sun: 227.9M km
Year: 687 days
Axial tilt: 25.19°
Moons: 2
Type: Terrestrial Planet

Size, to scale

Atmosphere

A thin cold sky

95% carbon dioxide, 2.8% nitrogen, 2% argon, with traces of oxygen and water vapour. Surface pressure is just 0.6% of Earth's — too thin for liquid water to be stable except in transient brines. Dust storms can grow to engulf the entire planet for weeks at a time.

Seen edge on, along the line between day and night.

Surface

Red dust and giant volcanoes

Vast volcanic plains, ancient riverbeds, polar ice caps of frozen water and CO₂, and impact craters. Recurring slope lineae — dark streaks that appear seasonally — were once thought to be flowing water but are now interpreted mostly as dry granular flows.

A close pass, stopped where the surface map runs out of detail.

Interior

Layers, drawn to scale

A partly molten silicate mantle and a liquid iron-sulfur core ~1,830 km in radius (confirmed by NASA's InSight lander seismic data, 2018–22). Mars lacks a global magnetic field today, though crustal magnetism preserves evidence of an ancient one.

Formation

How it formed

Formed roughly 4.5 billion years ago from the same protoplanetary disc as Earth. Its smaller size meant faster cooling — Mars lost most of its internal heat and atmospheric retention within its first billion years.

Orbit

Where Mars is today

Average distance from the Sun: 227.9 million km (1.52 AU). Eccentricity 0.0934 — its distance from the Sun varies considerably across the year. Axial tilt 25.19°, similar to Earth's, so Mars has seasons too.

Sunlight takes

13 min 1.7 s

to reach Mars, and its reflected light needs 13 min 27.4 s more to reach us.

Moons

Mars's major moons

Missions

Who has been to look

1965Mariner 4Past
First successful Mars flyby; killed off the canals-of-Mars hypothesis with cratered photographs.
2012–CuriosityActive
Climbing Mount Sharp in Gale crater, sampling sediments laid down when the crater held a lake.
2021–Perseverance / IngenuityActive
Caching samples for a future return mission; Ingenuity flew the first powered flight on another planet (now retired Jan 2024).

Go further

See it for yourself

Questions

Asked about Mars

How long would it take to get to Mars?

Roughly 6–9 months on a Hohmann transfer; the launch window opens about every 26 months.

Is there water on Mars?

Yes — abundant water ice in the polar caps and subsurface, plus seasonal frost. Liquid water is unstable on the surface today but flowed there billions of years ago.

How many moons does Mars have?

Two: Phobos and Deimos. Both are small, irregularly shaped, and likely captured asteroids.

Other bodies

Sources & methodology

Numbers cross-referenced with the sources below; surface and atmosphere descriptions reflect findings as of October 2026. Renderings in the 3D viewer use textures based on Solar System Scope and NASA imagery.