Mars is red because it is rusty. Its dust is full of iron oxide, the same stuff that coats an old bike left in the rain.
It is home to Olympus Mons, a volcano about 22 km tall, two and a half times the height of Everest. Its canyon, Valles Marineris, would stretch from New York to Los Angeles.
Mars was once wet. Rovers have driven across dried-up riverbeds and lake floors, which is why we keep looking for signs that something once lived there.
Its sunsets are blue. The fine red dust scatters the light the opposite way to Earth's air, so the sky glows blue around the setting Sun.
It has two tiny moons, Phobos and Deimos. Phobos is slowly spiralling inwards and will break apart in about 50 million years, maybe leaving Mars with a ring.
- Width
- 6,779 km
- One day
- 24.6 hours
- One year
- 687 Earth days
- Moons
- 2
- Temperature
- −65 °C on average
- 70 kg on Earth weighs
- 26 kg here
