This model of Mariner 10 shows the spacecraft as it appeared during flight. The Mariner 10 mission required more course corrections than any previous mission and was the first spacecraft to use the gravitational pull of one planet to help it reach another planet. This craft was also the first to use the solar wind as a means of locomotion; when the probe's thruster fuel ran low, scientists used the solar panels as sails to make course corrections. The Mariner Venus/Mercury mission (also known as Mariner 10) lasted from November 2, 1973 to March 24, 1975. Its purpose was to launch a single spacecraft toward Venus and, using the gravitational field of this planet to turn the probe into an heliocentric orbit, perform one (or several) fly-by of Mercury. This mission offers several major innovations : first Mercury flyby, first use of gravity-turn mission at one planet to reach another, first close-up pictures of Venus , first survey of solar plasma as close as Mercury, first comparison of Earth, Moon, Venus and Mercury with the same instruments first interplanetary -band (8500 MHz) tracking.