Mariner 9 spacecraft

Mariner 9 spacecraft

Courtesy of NASA

Mariner 9 was the first spacecraft to orbit another planet. Because of a large dust storm on Mars, Mariner 9 had to wait several months for the dust to settle before it could begin sending clear images. Although its mission ended in 1972 and communication stopped, Mariner 9 continues to orbit Mars. It is expected to burn up or crash into the Martian surface sometime around 2022.

May 30, 1971

November 14, 1971

End of Mission
October 27, 1972

Transmit images and measure UV and IR emissions.

After 349 days in orbit, Mariner 9 had transmitted 7,329 images, covering over 80% of Mars’ surface. The images revealed river beds, craters, massive extinct volcanoes, canyons. One of the canyons discovered was Valles Marineris, a massive system of canyons over 4,000 km (2,500 miles) named in honor of the spacecraft. Mariner 9 found evidence of wind and water erosion, weather fronts, and fog. It photographed Mars’ tiny moons, Phobos and Deimos. One of the largest global storms ever observed on Mars obscured all details except the summits of Olympus Mons and the three Tharsis volcanoes.