Zond 1 was a spacecraft of the Soviet Zond program. It was the second Soviet research spacecraft to reach Venus, although communications had failed by that time. It carried a spherical landing capsule, containing experiments for chemical analysis of the atmosphere, gamma-ray measurements of surface rocks, a photometer, temperature and pressure gauges, and a motion/rocking sensor in case it landed in water. An experimental Ion thruster was also carried for evaluation.

Spacecraft design

The Zond-1 was a 3MV design, the second generation inter-planetary Soviet bus, improving over the 2MV design used for previous Mars and Venus missions. However, more importantly, significant advancements were in the 8K78 Molniya launch vehicle whose Block-L (upper stage) had crippled half a dozen interplanetary missions before. The new version of the launch vehicle was named 8K78M Molniya.

On either side of the spacecraft, two solar panels were attached providing a total of about 4 meters squared of surface area. Attached to the ends of the solar panels were hemispherical radiators which provided thermal control to the spacecraft's internal systems. A 2 meter high-gain directional antenna was placed on the anti-sun side. Various low-gain antennas were placed throughout the spacecraft to provide omnidirectional communications capability.

Bus:

  • Radiation detector
  • Charged-particle detector
  • Magnetometer
  • Piezoelectric detector
  • Atomic hydrogen detector

Lander:

  • Barometer
  • Thermometer
  • Radiation detector
  • Micro-organism detection experiment
  • Atmospheric composition experiment
  • Acidity measurement experiment
  • Electro-conductivity experiment
  • Luminosity experiment

Mission

Launch

The spacecraft, a Venera 3MV-1 No.4, was launched on April 2, 1964, from Tyuratam and this time the launch vehicle performed flawlessly. After the launch, during the spacecraft's first communications session, ground controllers detected a leak that was letting air escape from the pressurized orbital compartment. The orbital compartment housed all of the electronics of the bus which required to be pressurized to function. This was a serious problem as Soviet electronics relied on vacuum tubes which would overheat without cooling air. Using the leak's spin on the spacecraft, the ground crew determined that the leak originated from a bad weld near the quartz window for the probe’s star and Sun sensors and that the orbital compartment would be completely depressurized in just 1 week. 1 Day after launch, the first mid-course correction was completed successfully., forcing ground controllers to place Zond 1 into a spin-stabilization mode. Communication with the spacecraft could be maintained until mid-June, a full month before the Venus flyby, when the spacecraft would be too far away to receive its signals from the lander's antennas. However, all communications had failed by May 24. It passed from Venus on July 14, 1964

Naming

Zond missions were presented as engineering tests by the Soviet Union and to an extent at least that may have been the case.

See also

  • List of missions to Venus

References

  • Astrolink description of spacecraft and payload
  • NSSDC spacecraft info