Ranger 8 was a lunar probe in the Ranger program, a robotic spacecraft series launched by NASA in the early-to-mid-1960s to obtain the first close-up images of the Moon's surface. These pictures helped select landing sites for Apollo missions and were used for scientific study. During its 1965 mission, Ranger 8 transmitted 7,137 lunar surface photographs before it crashed into the Moon as planned. This was the second successful mission in the Ranger series, following Ranger 7. Ranger 8's design and purpose were very similar to those of Ranger 7. It had six television vidicon cameras: two full-scan and four partial-scan. Its sole purpose was to document the Moon's surface.

Spacecraft design

General

thumb|left|300px|Diagram of Ranger 8.

Ranger spacecraft were originally designed, beginning in 1959, in three distinct phases called "blocks". Rangers 6, 7, 8, and 9 were the Block 3 versions. The spacecraft consisted of a hexagonal aluminum frame base 1.5 m across on which was mounted the propulsion and power units, topped by a truncated conical tower that held the television cameras. Two solar panel wings, each 739 mm wide by 1537 mm long, extended from opposite edges of the base with a full span of 4.6 m, and a pointable high-gain dish antenna was hinge mounted at one of the corners of the base away from the solar panels. A cylindrical quasi-omnidirectional antenna was seated on top of the conical tower. The overall height of the spacecraft was 3.6 m. The cameras were arranged in two separate chains, or channels; each was self-contained with separate power supplies, timers, and transmitters, to afford the greatest reliability and probability of obtaining high-quality television pictures. No other experiments were carried on the spacecraft. The first image was taken at 9:34:32 UT at an altitude of 2510 km. Transmission of 7,137 photographs

See also

  • List of artificial objects on the Moon
  • List of missions to the Moon
  • Timeline of Solar System exploration

References

  • Lunar impact: A history of Project Ranger (PDF), R. Cargill Hall, 1977
  • Photographs from Ranger 8
  • Video from Ranger 8dead link