||This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. (January 2013)|
|Mission type||Planetary Science|
|Launch date||July 18, 1965 at 14:38:00 UTC|
|Mission highlight||Fly-by of Moon on
July 20, 1965
at distance of 9,200 km
|Homepage||NASA NSSDC Master Catalog|
|Semimajor axis||1 AU|
|Orbital period||500 d|
|f/106 mm Camera and TV system with automatic inflight film processing
Ultraviolet (0.25–0.35 µm and 0.19–0.27 µm) spectrograph
Infrared (3–4 µm) spectrograph
Radiation sensors (gas-discharge and scintillation counters)
Experimental ion engine
Zond 3 was a 1964 space probe sent toward Mars as a spacecraft test. It was a member of the Soviet Zond program sharing designation Zond, while being part of Mars 3MV project. It was unrelated to Zond spacecraft designed for manned circumlunar mission (Soyuz 7K-L1). Zond 3 completed a successful Lunar flyby, taking a number of good quality photographs for its time. It is believed that Zond 3 was initially designed as a companion spacecraft to Zond 2 to be launched to Mars during the 1964 launch window. The opportunity to launch was missed, and the spacecraft was launched on a Mars trajectory as a spacecraft test, even though Mars was no longer attainable.
Spacecraft design 
The spacecraft design was similar to Zond 2, in addition to the imaging equipment it carried a magnetometer, ultraviolet (0.25 to 0.35 micrometre and 0.19 to 0.27 micrometre) and infrared (3 to 4 micrometre) spectrographs, radiation sensors (gas-discharge and scintillation counters), a radiotelescope and a micrometeoroid instrument. It also had an experimental ion engine.
The spacecraft, a Mars 3MV-4A, was launched from a Tyazheliy Sputnik (65-056B) earth orbiting platform towards the Moon and interplanetary space. The spacecraft was equipped with an f/106 mm camera and TV system that provided automatic inflight film processing. On July 20 lunar flyby occurred approximately 39 hours after launch at a closest approach of 9200 km. 23 photographs and 3 ultraviolet spectra of very good quality were taken of the lunar farside from distances of 11,570 to 9960 km over a period of 68 minutes. The photos covered 19,000,000 km² of the lunar surface. Zond 3 proceeded on a Mars trajectory, but not at a time when planetary encounter would occur. To test telemetry, the images were rewound and transmitted at 2.2 million km, 31.5 million km and possibly again at greater distances, thus proving the ability of the communications system. The mission was ended and radio contact ceased when it was at a distance of 150 million km.
This article was originally based on material from NASA (NSSDC) information on Zond 3
|Zond program (interplanetary)||Succeeded by