27 Listen and read. Mars is the fourth planet from the Sun and it has got two moons. People call it the Red Planet because most of its surface looks red. Mars hasn't got any blue oceans or green land. Length of Day and Year A day on Mars is 24 hours and 39 minutes long, a bit longer than a day on Earth. A year on Mars is 687 days! Seasons Mars has got four seasons like Earth, but they are different. Summers on Mars are not hot at all - in fact, they are -5 degrees Celsius. Brrr! Olympus Mons The largest mountain in the solar system is on Mars! It is more than 25 kilometres high-three times higher than Mount Everest!
