• Launch date: 25 February 1969
• Orbital insertion: 31 July 1969
• End of mission: 23 December 1970
• Agency: NASA
Originally built as a backup to the Mariner 4 spacecraft, which successfully journeyed to Mars in 1965, Mariner 5 was modified to fly by Venus and collect data on the planet’s atmosphere, radiation and magnetic field.
The spacecraft’s flight path following its Venus encounter brought it closer to the sun than any previous mission.