Mariner 5 Credit - NASA

Mariner 5 was a refurbished backup spacecraft for the Mariner 4 Mars mission converted to fly a Venus mission. Mariner 5 carried a complement of experiments to probe Venus's atmosphere with radio waves, scan its brightness in ultraviolet light, and sample the solar particles and magnetic field fluctuations above the planet.

The spacecraft was fully attitude stabilized, using the sun and Canopus as references. A central computer and sequencer subsystem supplied timing sequences and computing services for other spacecraft subsystems. The octagonal bus structure had four solar panels and was 3-axis stabilized using cold gas thrusters. S-Band communications via were via either the low gain or high gain antenna. A thermal shield protected the spacecraft from solar radiation. The spacecraft instruments measured both interplanetary and Venusian magnetic fields, charged particles, and plasmas, as well as the radio refractivity and UV emissions of the Venusian atmosphere. The mission was termed a success.

Typical orbit: Solar orbit - Venus flyby. Mass: 244 kg (537 lb).

• 1967 June 14 - Mariner 5 - Program: Mariner. Launch Site: Cape Canaveral. Launch Complex: LC12. Launch Vehicle: Atlas. Mass: 244 kg (537 lb).
  Mariner 5 flew by Venus on October 19, 1967 at an altitude of 3,990 kilometres. With more sensitive instruments than its predecessor Mariner 2, Mariner 5 was able to shed new light on the hot, cloud-covered planet and on conditions in interplanetary space. Operations of Mariner 5 ended in November 1967. The spacecraft instruments measured both interplanetary and Venusian magnetic fields, charged particles, and plasmas, as well as the radio refractivity and UV emissions of the Venusian atmosphere.

• 1967 October 19 - Mariner 5 Flyby of Venus -