Here the Mariner 10 spacecraft is being assembled prior to its November
1973 launch. During its two-year mission, the spacecraft transmitted
over 12,000 images of Mercury and Venus. The mission ended in March
1975. Mariner 10 is still orbiting the sun, even though its electronic
systems have probably been destroyed by solar radiation.
A nighttime lift-off of the Atlas Centaur launch vehicle propelled
Mariner 10 on its historic mission to Venus and Mercury. Launched in
November 1973, the mission lasted until March 1975 when the spacecraft
was shut down and placed in orbit about the sun.
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.
Mariner 10, shown in this artist's rendering, was the last in a series
of Mariner missions designed to survey other planets in the solar
system. Launched in November 1973, this mission provided new
information about Mercury and Venus in the Mariner program's first
dual-planet mission. On February 5, 1974, Mariner 10 made its first
flyby of Venus and discovered evidence of rotating clouds. Beginning in
March 1974, Mariner 10's three flybys past Mercury mapped about half of
the planet's surface, during which time a thin atmosphere and a
magnetic field were discovered.