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planet · inner rocky planet

Mars

The red one. You can find it with your own eyes. Mars has Olympus Mons — a volcano 3× taller than Mount Everest! The whole planet is about half the width of Earth.

Also called: the Red Planet.

🕒 When can I see it?🚀 Travel there
Mars — Drawn, not photographed.

What it is

The Red Planet, thin CO2 atmosphere, tallest volcano in the solar system, dry riverbeds.

Planet: Round, orbits a star, and has swept its orbit clear. Every kind of thing there is →

How to find Mars

Its position moves, so there is no fixed place on a map to point at. The Planetarium works out where it is for your own place and date.

Show me Mars in tonight's sky

What you will really see

With your own eyes

A steady orange-red point that doesn't twinkle like the stars around it.

Through a small telescope

A small orange dot; on a steady night, dark patches and a white polar cap.

🔭 See it drawn as it looks through a telescope
🖨️ A sheet to print for this
🖨️ Print a sheet and go and look
🖨️ Sheet to take outside →

Worth knowing about Mars

Mars is about half the size of Earth. In weight, light — about 1/9th of Earth. One and a half times Earth's distance from the Sun. Sunlight takes 13 minutes to reach Mars — on average, because that distance changes as it goes round. Almost two Earth years — you'd have two birthdays before Mars finished one lap around the Sun. Mars spins all the way around in about 24 hours 37 minutes — close to Earth's day. The sunrise-to-sunrise day (Mars scientists call it a 'sol') is a touch longer still, about 24 hours 40 minutes, for the same catching-up reason as Earth.

What it is made of
Rocky, red iron-oxide dust ('rust'), tallest volcano in the solar system, ancient dry riverbeds.
Its weather
Thin CO2 atmosphere, planet-wide dust storms, average -60C.
The machines we sent
Perseverance rover is exploring right now, searching for signs of past life.
How did anyone measure the Earth in the first place?
The numbers
Across6 779 km
Distance from the Sun, on average1.5 AU ~228 million km · sunlight takes 13 minutes
Once round its orbit1.9 Earth years
One day there24.7 hours
Temperature-60 °C (from -153 to 20)
Made of, among other thingscarbon dioxide, water, rock (basalt)

How anyone knows this

Nobody flew a tape measure out there. Every number on this page was worked out from the ground:

What it belongs to

☀️ Everything the Sun holds, in one place📖 How the solar system fits together

Then go outside

Clear tonight? The Planetarium will show you what is worth a look. Then just go out.

🌙 Plan an evening outside🌌 Everything else in the sky