Gemini 12 (officially Gemini XII)
[ With Gemini IV, NASA changed to Roman numerals for Gemini mission designations.] was a 1966
crewed spaceflight in
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeedin ...
's
Project Gemini
Project Gemini () was NASA's second human spaceflight program. Conducted between projects Mercury and Apollo, Gemini started in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual ...
. It was the 10th and final crewed Gemini flight (
Gemini 1 and
Gemini 2
Gemini 2 (Gemini-Titan 2; GT-2) was the second spaceflight of the American human spaceflight program Project Gemini, and was launched and recovered on January 19, 1965. Gemini 2, like Gemini 1, was an uncrewed mission intended as a test fligh ...
were uncrewed missions), the 18th crewed American spaceflight, and the 26th spaceflight of all time, including
X-15 flights over . Commanded by
Gemini VII
Gemini 7 (officially Gemini VII) With Gemini IV, NASA changed to Roman numerals for Gemini mission designations. was a 1965 crewed spaceflight in NASA's Gemini program. It was the fourth crewed Gemini flight, the twelfth crewed American space ...
veteran
James A. Lovell, the flight featured three periods of
extravehicular activity
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA inc ...
(EVA) by rookie
Edwin "Buzz" Aldrin, lasting a total of 5 hours and 30 minutes. It also achieved the fifth
rendezvous and fourth
docking with an
Agena target vehicle.
Gemini XII marked a successful conclusion of the Gemini program, achieving the last of its goals by successfully demonstrating that astronauts can effectively work outside of spacecraft. This was instrumental in paving the way for the
Apollo program to achieve its goal of landing a man on the Moon by the end of the 1960s.
Crew
Backup crew
Support crew
*
Stuart A. Roosa (Cape CAPCOM)
*
Charles "Pete" Conrad Jr. (Houston CAPCOM)
*
William A. Anders (Houston CAPCOM)
Mission parameters
*
Mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different ele ...
:
*
Perigee
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion.
General description
There are two apsides in any el ...
:
*
Apogee
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion.
General description
There are two apsides in any el ...
:
*
Inclination
Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object.
For a satellite orbiting the Ea ...
: 28.87°
*
Period: 88.87 min
Docking
*Docked: November 12, 1966 - 01:06:00 UTC
*Undocked: November 13, 1966 - 20:18:00 UTC
Space walk
* Aldrin - EVA 1 - (stand up)
**Start: November 12, 1966, 16:15:00 UTC
**End: November 12, 1966, 18:44:00 UTC
**Duration: 2 hours, 29 minutes
* Aldrin - EVA 2
**Start: November 13, 1966, 15:34:00 UTC
**End: November 13, 1966, 17:40:00 UTC
**Duration: 2 hours, 06 minutes
* Aldrin - EVA 3 (stand up)
**Start: November 14, 1966, 14:52:00 UTC
**End: November 14, 1966, 15:47:00 UTC
**Duration: 0 hours, 55 minutes
Launch
Liftoff of the Atlas/Agena Target Vehicle occurred at 2:07:59 PM EST, and of the Gemini/Titan spacecraft at 3:46:33 PM EST, on November 11.
All launch vehicle systems performed nominally during powered flight, but at staging there was a recurrence of the first stage oxidizer tank rupture first seen on
Gemini 10's launch. On Gemini 12, the fuel tank appeared to have also ruptured as a white cloud was seen emitting from the spent stage along with the orange
nitrogen tetroxide. Another episode of "Green Man" also occurred at SECO, referring to pitch gyrations caused by pressure buildup in the second stage protective skirt.
Objectives
At the completion of the previous Gemini flight, the program still had not demonstrated that an astronaut could work easily and efficiently outside the spacecraft. Prior to the Gemini XII mission, other astronauts from previous missions of the
Gemini Program
Project Gemini () was NASA's second human spaceflight program. Conducted between projects Mercury and Apollo, Gemini started in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual ...
had attempted
EVAs. However, their successes were limited due to a lack of proper restraints and insufficient techniques.
In preparation for Gemini XII new, improved restraints were added to the outside of the capsule, and a new technique—underwater training—was introduced, which would become a staple of future space-walk simulation. The main purpose of the Gemini XII mission was to find and test new ways to work outside of a spacecraft safely and effectively.
Aldrin's two-hour, 20-minute tethered space-walk, during which he photographed star fields, retrieved a micrometeorite collector and did other chores, at last demonstrated the feasibility of extravehicular activity. Two more stand-up EVAs also went smoothly, as did the by-now routine rendezvous and docking with an Agena which was done "manually" using the onboard computer and charts when a rendezvous radar failed. The climb to a higher orbit, however, was canceled because of a problem with the
Agena booster.
During orbital injection, the GATV engine experienced a drop in turbopump speed lasting about 2.5 seconds. After this, pump performance returned to normal. Telemetry data indicated erratic pump speeds, but engine performance did not reflect this. The anomaly was later found as a brief 30 psi drop in the thrust chamber of the rocket. The mission had planned for an orbital maneuver into a higher orbit but the drop in pressure raised some concerns. Ground controllers decided not to risk the planned orbital boost maneuver since the exact reason for the pump slowdown was unclear. Following Gemini 12's reentry and during the GATV's 63rd orbit, they attempted to fire the propulsion system, but a stuck fuel valve prevented engine start from occurring.
It was suspected that a turbopump bearing failure caused the anomalous conditions during orbital injection, followed by heating and melting of pump components. The inability of ground controllers to start the engine during the 63rd orbit was possibly due to melted or loose debris blocking the fuel valve and preventing its operation. The telemetry data falsely reporting erratic pump speed was concluded to be debris being knocked around and affecting the data probes.
The 1994 book and documentary ''
Moon Shot
''Moon Shot: The Inside Story of America's Race to the Moon'' is a 1994 book written by Mercury Seven astronaut Alan Shepard, with NBC News correspondent Jay Barbree and Associated Press space writer Howard Benedict. Astronaut Donald K. "De ...
'', as well as the 2008 documentary ''
When We Left Earth: The NASA Missions'', credits the
spacewalk
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA in ...
innovations, including the
underwater training, to Aldrin himself.
Gemini 12 was designed to perform rendezvous and docking with the Agena target vehicle, to conduct three
extra-vehicular activity (EVA) operations, to conduct a tethered stationkeeping exercise, to perform docked maneuvers using the Agena propulsion system to change orbit, and demonstrate an automatic reentry.
When Gemini 12 was being planned, one of the possibilities raised was the potential for the flight to be run in conjunction with the
first Apollo mission, which had been tentatively scheduled for the last quarter of 1966. By May 1966, delays in making Apollo ready for flight just by itself, and the extra time needed to incorporate compatibility with the Gemini, made that impractical. This became moot when slippage in readiness of the
Apollo spacecraft caused the last-quarter 1966 target date to be missed, and the Apollo mission was rescheduled for February 21, 1967.
Experiments
The 14 scientific experiments were (1) frog egg growth under zero-g, (2) synoptic terrain photography, (3) synoptic weather photography, (4) nuclear emulsions, (5) airglow horizon photography, (6) UV astronomical photography, and (7) dim sky photography. Two micrometeorite collection experiments, as well as three space phenomena photography experiments, were not fully completed.
Reentry
The capsule was controlled on reentry by computer and splashed down 4.8 kilometers from its target. The crew were taken aboard the aircraft carrier .
The Gemini 12 mission was supported by the following U.S. Department of Defense resources; 9,775 personnel, 65 aircraft and 12 ships.
Postflight medical examination disclosed no unusual conditions in either astronaut. Both were slightly exhausted and dehydrated due to problems with the spacecraft's water supply system forcing them to reduce their fluid intake on the last day of the mission and Lovell had a mild case of
pinkeye.
Insignia
The patch's unique orange and black colors are a link to the flight's original scheduled date close to Halloween. The Roman numeral XII is located at the 12 o'clock position on the face of a clock, with the Gemini spacecraft pointing to it like the hour hand of a clock. This represents the position of Gemini 12 as the last flight of the Gemini program. With the Apollo project following this last flight of the Gemini program, the ultimate objective—the Moon—is symbolized by the crescent on the left.
Spacecraft location
After several years at the
Museum of Transport and Technology, in
Auckland
Auckland (pronounced ) ( mi, Tāmaki Makaurau) is a large metropolitan city in the North Island of New Zealand. The most populous urban area in the country and the fifth largest city in Oceania, Auckland has an urban population of about I ...
, New Zealand, the spacecraft was returned to the United States. It is now on display at the
Adler Planetarium,
Chicago, Illinois
(''City in a Garden''); I Will
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. Lovell and Aldrin were reunited with the spacecraft November 9, 2006 during the opening for Adler's "Shoot for the Moon" exhibit, almost 40 years after the mission launched.
See also
*
Agena Target Vehicle
*
Extra-vehicular activity
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA in ...
*
List of spacewalks
Lists of spacewalks and moonwalks include:
By date:
* List of spacewalks and moonwalks 1965–1999
* List of spacewalks 2000–2014
* List of spacewalks since 2015
By space station:
* List of Salyut spacewalks
* List of Mir spacewalks
* List o ...
*
Splashdown
*
Solar eclipse of November 12, 1966
*
Space suit
A space suit or spacesuit is a garment worn to keep a human alive in the harsh environment of outer space, vacuum and temperature extremes. Space suits are often worn inside spacecraft as a safety precaution in case of loss of cabin pressure, ...
References
External links
NASA Gemini 12 press kit - Nov 3, 1966Gemini 12 Mission Report (PDF) January 1967*
NASA Space Science Data Coordinated Archive*U.S. Space Objects Registry https://web.archive.org/web/20090521121750/http://usspaceobjectsregistry.state.gov/search/index.cfm
{{Authority control
Buzz Aldrin
Extravehicular activity
Human spaceflights
Project Gemini missions
Spacecraft launched in 1966
Spacecraft launched by Titan rockets
November 1966 events
Jim Lovell