What did Mariner 10 see during its historic journey to Venus and Mercury?
Mariner 10 was the first spacecraft sent to the planet Mercury, the first mission to explore two planets during a single mission, the first to use a gravity assist to change its flight path, the first to return to its target after an initial encounter and the first to use the solar wind as a major means of spacecraft orientation during flight.
But what did it capture with its two onboard cameras?
Mariner 10 was launched by NASA on 3 November 1973, to fly by the planets Mercury and Venus. It was the first spacecraft to perform flybys of multiple planets.
Mariner 10 was launched approximately two years after Mariner 9 and was the last spacecraft in the Mariner program. (Mariner 11 and Mariner 12 were allocated to the Voyager program and redesignated Voyager 1 and Voyager 2.)
The mission objectives were to measure Mercury's environment, atmosphere, surface, and body characteristics and to make similar investigations of Venus. Secondary objectives were to perform experiments in the interplanetary medium and to obtain experience with a dual-planet gravity assist mission.
Mariner 10's science team was led by Bruce C. Murray at the Jet Propulsion Laboratory.