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Gemini 6



Gemini 6 was planned to be the third manned Earth orbiting spacecraft of the Gemini series. Its primary mission involved rendezvous with a Gemini-Agena target vehicle (GATV) after completion of synchronized countdown procedures for both vehicles. The flight was cancelled after the GATV failed to orbit. The Gemini 6 vehicle was rescheduled, and redesignated as Gemini 6-A, (65-104A).

Spacecraft and Subsystems

The Gemini spacecraft was a cone-shaped capsule consisting of two components, a reentry module and an adaptor module. The adaptor module made up the base of the spacecraft. It was a truncated cone 228.6 cm high, 304.8 cm in diameter at the base and 228.6 cm at the upper end where it attached to the base of the reentry module. The re-entry module consisted of a truncated cone which decreased in diameter from 228.6 cm at the base to 98.2 cm, topped by a short cylinder of the same diameter and then another truncated cone decreasing to a diameter of 74.6 cm at the flat top. The reentry module was 345.0 cm high, giving a total height of 573.6 cm for the Gemini spacecraft.

The adaptor module was an externally skinned, stringer framed structure, with magnesium stringers and an aluminum alloy frame. The adaptor was composed of two parts, an equipment section at the base and a retrorocket section at the top. The reentry module consisted mainly of the pressurized cabin designed to hold the two Gemini astronauts. Two instrumentation pallets were mounted in place of the couches which would normally hold the astronauts. The pallets carried some 180 kg of pressure transducers, temperature sensors, and accelerometers. Separating the reentry module from the retrorocket section of the adaptor at its base was a curved silicone elastomer ablative heat shield. The module was composed predominantly of titanium and nickle-alloy with beryllium shingles. Dummy packages and ballast was used to simulate normal spacecraft weight and configuration for systems not required for this flight.

Gemini Program

The Gemini program was designed as a bridge between the Mercury and Apollo programs, primarily to test equipment and mission procedures in Earth orbit and to train astronauts and ground crews for future Apollo missions. The general objectives of the program included: long duration flights in excess of of the requirements of a lunar landing mission; rendezvous and docking of two vehicles in Earth orbit; the development of operational proficiency of both flight and ground crews; the conduct of experiments in space; extravehicular operations; active control of reentry flight path to achieve a precise landing point; and onboard orbital navigation. Each Gemini mission carried two astronauts into Earth orbit for periods ranging from 5 hours to 14 days. The program consisted of 10 crewed launches, 2 uncrewed launches, and 7 target vehicles, at a total cost of approximately 1,280 million dollars.

Alternate Names

  • Gemini6

Facts in Brief

Launch Date: 1965-10-25
Launch Vehicle: Atlas-Agena D
Launch Site: Cape Canaveral, United States
Mass: 3261 kg

Funding Agency

  • NASA-Office of Manned Space Flight (United States)


  • Engineering

Additional Information

Questions and comments about this spacecraft can be directed to: Dr. David R. Williams



NameRoleOriginal AffiliationE-mail
Dr. Charles W. MathewsProject ManagerNASA Headquarters
Dr. William C. SchneiderProject ManagerNASA Headquarters
Dr. George E. MuellerProgram ManagerNASA

Selected References

  • Gemini midprogram conference including experimental results, NASA, SP-121, 1966. (Papers Presented at the Manned Spaceflight Center, Houston, Feb. 23-25, 1966)
  • Gemini summary conference, NASA, SP-138, Wash, DC, Feb. 1967.
  • Grimwood, J. M., et al., Project Gemini technology and operations - A chronology, NASA, NASA SP-4002, Wash., DC, 1969.

Gemini 6A
Gemini 7
Gemini 6 Target - failed

Gemini Home Page
Chronology of U.S. Astronaut Missions - Mercury, Gemini, and Apollo

Gemini Books Online

On The Shoulders of Titans: A History of Project Gemini - NASA History Office
Project Gemini Technology and Operations - A Chronology - NASA History Office

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