Mars is smaller than both Earth and Venus. The first spacecraft to visit Mars was Mariner 4 in 1965. Several others followed, most recently in 2008, when Phoenix landed in the northern plains to search for water. Three Mars orbiters (Mars Reconnaissance Orbiter, Mars Odyssey, and Mars Express) are also currently at work studying Mars.
NASA has landed several unmanned robotic probes on Mars, most recently two remote controlled car-like robots called Mars Rovers. These probes allow NASA scientists to explore the planet, take pictures, analyse soil and conduct experiments. The picture on the left is of one of the Mars Rovers on the surface of Mars.
Mars is named after the Greek God of War. It is sometimes also called the red planet, because most of its surface is covered in reddish rocks, dust and soil.
Mars is 228,000,000 km away from the sun.
