Zond 3 was a 1965

space probe A space probe is an artificial satellite that travels through space to collect scientific data. A space probe may orbit Earth; approach the Moon; travel through interplanetary space; flyby, orbit, or land or fly on other planetary bodies; o ...

which performed a flyby of the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

far side, taking a number of quality photographs for its time. It was a member of the

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

Zond program Zond (russian: Зонд, lit=probe) was the name given to two distinct series of Soviet robotic spacecraft launched between 1964 and 1970. The first series, based on the 3MV planetary probe, was intended to gather information about nearby plan ...

while also being part of the Mars 3MV project. It was unrelated to Zond spacecraft designed for manned circumlunar missions (

Soyuz 7K-L1 The Soyuz 7K-L1 "Zond" spacecraft was designed to launch men from the Earth to circle the Moon without going into lunar orbit in the context of the Soviet crewed Moon-flyby program in the Moon race. It was based on the Soyuz 7K-OK. Several ...

). It is believed that Zond 3 was initially designed as a companion spacecraft to

Zond 2 Zond 2 was a Soviet space probe, a member of the Zond program, and was the sixth Soviet spacecraft to attempt a flyby of Mars. (See Exploration of Mars) It was launched on November 30, 1964 at 13:12 UTC onboard Molniya 8K78 launch vehicle fro ...

to be launched to Mars during the 1964 launch window. The opportunity to launch was missed, and the spacecraft was launched on a Mars-crossing trajectory as a spacecraft test, even though Mars was no longer attainable.

Spacecraft design

The spacecraft was of the 3MV-4 type, similar to

. In addition to a 106.4 mm focal length imaging system for visible light photography and

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation ...

spectrometry at 285-355 μm, it carried ultraviolet (190-275 μm) and

infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of Light, visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from ...

(3-4 μm) spectrophotometers, radiation sensors ( gas-discharge and

scintillation counter A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillating material, and detecting the resultant light pulses. It consists of a scintillator wh ...

s), charged particle detector,

magnetometer A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, ...

, and

micrometeoroid A micrometeoroid is a tiny meteoroid: a small particle of rock in space, usually weighing less than a gram. A micrometeorite is such a particle that survives passage through Earth's atmosphere and reaches Earth's surface. The term "micrometeor ...

detector. It also had an experimental

ion engine An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of ...

Operational history

Zond 3 was launched from

Baikonur Cosmodrome ''Baiqoñyr ğaryş ailağy'' rus, Космодром Байконур''Kosmodrom Baykonur'' , image = Baikonur Cosmodrome Soyuz launch pad.jpg , caption = The Baikonur Cosmodrome's "Gagarin's Start" Soyuz ...

on July 18, 1965, at 14:38 UTC, and was deployed from a

Tyazhely Sputnik Tyazhely Sputnik (russian: Тяжёлый Спутник, meaning ''Heavy Satellite''), also known by its development name as Venera 1VA No. 1, and in the West as Sputnik 7, was a Soviet spacecraft, which was intended to be the first sp ...

(65-056B) Earth-orbiting platform towards the

and interplanetary space. This was a repeat of a mission that failed in late 1963 intended to test communication at distances equivalent to the distances experienced by Mars and Earth. Zond 3's lunar flyby occurred on July 20 with a closest approach of , approximately after launch. 25 visible light photographs and 3 ultraviolet spectra of very good quality were taken of the lunar surface, beginning at 01:24 UTC and prior to closest approach and ending at 02:32 UTC and past closest approach, covering a period of 68 minutes. The photos covered of the lunar surface. Zond 3 proceeded on a trajectory across Mars' orbit, but not at a time when planetary encounter would occur. These images were transmitted by radio frequency on July 29 at a distance of . To test telemetry, the camera film was rewound and retransmitted in mid-August, mid-September, and finally on October 23 at a distance of , thus proving the ability of the communications system. The subsequent transmissions were also at progressively slower data rates but higher quality. The mission was ended after radio contact ceased on March 3, 1966, when it was at a distance of . It operated for 228 days, roughly equivalent to the time needed to survive a journey to Mars and exceeding that needed for Venus.

References

* ''This article was originally based on material fro
NASA (NSSDC) information on Zond 3
'

External links

Zond 3
at Zarya.info

at Mentallandscape.com {{Use mdy dates, date=June 2018 Zond program Derelict satellites in heliocentric orbit Spacecraft launched in 1965 1965 in the Soviet Union Lunar flybys