Several man-made satellites have been sent to Mars since 1964. The first spacecraft to Mars, known as Mariner 3, was launched on Nov. 5, 1964. This spacecraft malfunctioned and failed to fly by Mars as planned.
The Mariner 4, was launched on Nov. 28, 1964, for an eight-month journey to Mars, followed by Mariner 6 and Mariner 7, launched in 1969; Mariner 8 and 9, launched in 1971, and Viking 1 and 2, launched in 1976. Other missions to Mars include the Mars Observer of 1992, Mars Pathfinder of 1996, Mars Climate Orbiter of 1998 and Phoenix, which was sent to Mars on Aug. 4, 2007.