An imaginary journey to Mars provides facts about the planet's year, atmosphere, size, gravity and geography, and suggests some of the questions scientists would want to answer if they were to travel there.

Imagine you could go -- Years and days -- Atmosphere -- Size -- Surface -- Gravity -- Tall land -- Volcanoes -- Plains -- Canyons and craters -- The South Pole -- How do scientists know about Mars? -- Mars facts -- Words to know.