Mission type | |
---|---|
Operator | NASA |
COSPAR ID | 1966-020A |
SATCAT no. | 2105 |
Mission duration | 10 hours, 41 minutes, 26 seconds |
Distance travelled | 293,206 kilometers (158,319 nautical miles) |
Orbits completed | 6 |
Spacecraft properties | |
Spacecraft | Gemini SC8 |
Manufacturer | McDonnell |
Launch mass | 3,789 kilograms (8,353 lb) |
Crew | |
Crew size | 2 |
Members | |
Start of mission | |
Launch date | March 16, 1966, 16:41:02 UTC |
Rocket | Titan II GLV,s/n 62-12563 |
Launch site | Cape Kennedy LC-19 |
End of mission | |
Recovered by | USS Leonard F. Mason |
Landing date | March 17, 1966, 03:22:28 UTC |
Landing site | 25°14′N136°0′E / 25.233°N 136.000°E |
Orbital parameters | |
Reference system | Geocentric |
Regime | Low Earth orbit |
Perigee altitude | 261 kilometers (141 nmi) |
Apogee altitude | 270 kilometers (150 nmi) |
Inclination | 28.9 degrees |
Period | 89.81 minutes |
Epoch | March 16, 1966 [1] |
Docking with GATV-5003 | |
Docking date | March 16, 1966, 23:14 UTC |
Undocking date | March 16, 1966, ~23:45 UTC |
Time docked | ~30 minutes |
(L-R) Scott, Armstrong |
Gemini 8 (officially Gemini VIII) [2] was the sixth crewed spaceflight in NASA's Gemini program. It was launched on March 16, 1966, and was the 14th crewed American flight and the 22nd crewed spaceflight overall. [lower-alpha 1] The mission conducted the first docking of two spacecraft in orbit, but also suffered the first critical in-space system failure of a U.S. spacecraft which threatened the lives of the astronauts and required an immediate abort of the mission. The crew returned to Earth safely.
Command pilot Neil Armstrong resigned his commission in the U.S. Naval Reserve in 1960, and was selected as a crew member for Gemini 8 in September 1965. His flight marked the second time a U.S. civilian flew into space (after Joe Walker on X-15 Flight 90), [3] [4] [lower-alpha 2] and the first time a U.S. civilian flew into orbit.
Position | Astronaut | |
---|---|---|
Command Pilot | Neil A. Armstrong First spaceflight | |
Pilot | David R. Scott First spaceflight |
Position | Astronaut | |
---|---|---|
Command Pilot | Charles "Pete" Conrad Jr. | |
Pilot | Richard F. Gordon Jr. | |
This became the prime crew on Gemini 11. |
March 16, 1966
Gemini VIII was planned to be a three-day mission. After being launched into an 87-by-146-nautical-mile (161 by 270 km) orbit, on the fourth revolution it was to rendezvous and dock with an Agena target vehicle, which had been earlier launched into a 161-nautical-mile (298 km) circular orbit. This was to be the first space docking in history. Four separate dockings were planned. [6]
During the first docking, Pilot David Scott planned to perform an ambitious, two-hour-and-10-minute extra-vehicular activity (EVA), which would have been the first since Ed White's June 1965 spacewalk on Gemini IV. On a 25-foot (7.6 m) tether for one and a half revolutions around the Earth, Scott would have retrieved a nuclear emulsion radiation experiment from the front of the Gemini's spacecraft adapter, then activate a micrometeoroid experiment on the Agena. Then he was to move back to the Gemini and test a minimum-reaction power tool by loosening and tightening bolts on a work panel. [6]
During the EVA, after Armstrong undocked from the Agena, Scott was to don and test an Extravehicular Support Pack (ESP) stored at the back of the spacecraft adapter. This was a backpack with a self-contained oxygen supply, extra Freon propellant for his Hand Held Maneuvering Unit, and a 75-foot (23 m) extension to his tether. He would practice several maneuvers in formation with the Gemini and Agena vehicles (separated at distances up to 60 feet (18 m), in concert with Armstrong in the Gemini. [7]
The flight also carried an additional three scientific, four technological, and one medical experiment. [8]
Five months earlier, NASA had launched an Agena Target Vehicle for Gemini 6, but the Atlas-Agena launch failed when the Agena's engine exploded during orbital injection and the mission had to be rescheduled. The next attempt succeeded. Everything worked perfectly; the Agena put itself into a 161-nautical-mile (298 km) circular orbit and oriented itself to the correct attitude for the docking.
The Gemini spacecraft was launched into an 86-by-147-nautical-mile (159 by 272 km) orbit by a modified Titan II on March 16, 1966 (coincidentally the 40th anniversary of the launch of the world's first liquid-fueled rocket by Dr. Robert H. Goddard), at 10:41:02 a.m. EST. Gemini 8's launch was nominal and no significant anomalies occurred with either the Titan II or the spacecraft.
Gemini 8 Agena info | |
---|---|
Target vehicle | GATV-5003 |
NSSDC ID: | 1966-019A |
Mass | 3,175 kilograms (7,000 lb) |
Launch site | LC-14 |
Launch date | March 16, 1966 |
Launch time | 15:00:03 UTC |
1st perigee | 299.1 kilometers (161.5 nmi) |
1st apogee | 299.7 kilometers (161.8 nmi) |
Period | 90.47 m |
Inclination | 28.86 |
Reentered | September 15, 1967 |
Their first course adjustment was made at one hour and 34 minutes into the mission, when the astronauts lowered their apogee slightly with a five-second Orbit Attitude and Maneuvering System (OAMS) thruster burn. The second adjustment was made near apogee of the second orbit, and raised both the apogee and perigee by adding 49 feet per second (15 m/s) to their speed. The third adjustment was made over the Pacific Ocean, a southward orbital plane change, made with a 59 feet per second (18 m/s) sideways thruster burn. When they were over Mexico, Jim Lovell, the Houston capsule communicator, told them they needed one last correction, a 2.6 feet per second (0.79 m/s) speed addition.
The rendezvous radar acquired the Agena Target Vehicle at a distance of 179 nautical miles (332 km). At 3 hours, 48 minutes and 10 seconds into the mission they performed another burn that put them in a circular orbit 15 nautical miles (28 km) below the Agena. They first sighted it when they were 76 nautical miles (141 km) away, and at 55 nautical miles (102 km) they gave the computer automatic control.
After several small burns they were 151 feet (46 m) away and with no relative velocity. After 30 minutes of visually inspecting the Agena to make sure that it had not been damaged by the launch, they were given the go for docking. Armstrong started to move towards the Agena at 3.15 inches (8 centimeters) per second. In a matter of minutes, the Agena's docking latches clicked and a green light indicated that the docking had been successfully completed. "Flight, we are docked! Yes, it's really a smoothie," Scott radioed to the ground.
There was some suspicion on the ground that the Agena's attitude control system was malfunctioning and might not have the correct program stored in it. This suspicion was found to be incorrect. Shortly before radio blackout, Mission Control cautioned the astronauts to immediately abort the docking if any abnormalities occurred with the Agena.
After the Agena began execution of its stored command program, which instructed the Agena to turn the combined spacecraft 90° to the right, Scott noticed that they were rolling. Armstrong used the Gemini's OAMS thrusters to stop the roll, but after it stopped, it immediately started again. Gemini 8 was out of range of ground communications at this time.
Armstrong reported that the OAMS fuel had dropped to 30%, indicating that the problem could be on their own spacecraft. With concern that the high rate of rotation might damage one or both spacecraft or even cause the propellant-heavy Agena to rupture or explode, the crew decided to undock from the Agena so they could analyze the situation. Scott switched the Agena control back to ground command, while Armstrong struggled to stabilize the combined vehicle enough to permit undocking. Scott then hit the undock button, and Armstrong fired a long burst of translation thrusters to back away from the Agena. Without the added mass of the Agena, Gemini started rotating more rapidly. The astronauts realized that the problem was on the Gemini. By now the tumble rate had reached 296 degrees per second and Armstrong decided to shut down the OAMS and use the Reentry Control System (RCS) thrusters, located on the Gemini's nose, to stop the tumble. From start to finish the incident lasted nearly 30 minutes. [9]
NASA turned off the squawk box at Armstrong's home, alarming his wife. Scott later praised Armstrong's actions as their spacecraft spun: "The guy was brilliant. He knew the system so well. He found the solution, he activated the solution, under extreme circumstances ... it was my lucky day to be flying with him." [10] The spacecraft came in range of the ground communications ship Coastal Sentry Quebec . After steadying the spacecraft, the crew tested each OAMS thruster in turn and found that Number 8 had stuck on. Almost 75% of the reentry maneuvering fuel had been used to stop the tumble, [11] and mission rules dictated that the flight be aborted once the Reentry Control System was fired for any reason. Gemini 8 immediately prepared for an emergency landing.
It was decided to let the spacecraft reenter one orbit later so that it could land in a place that could be reached by secondary recovery forces. The original plan was for Gemini 8 to land in the Atlantic, but that was supposed to be three days later. USS Leonard F. Mason started to steam towards the new landing site 800 kilometers (430 nmi; 500 mi) east of Okinawa and 1,000 kilometers (540 nmi; 620 mi) south of Yokosuka, Japan.
Reentry took place over China, out of range of NASA tracking stations.
Planes were also dispatched, and U.S. Air Force pilot Les Schneider spotted the spacecraft as it descended precisely on time and on target. Three pararescuers jumped from their C-54 and attached a flotation collar to the capsule. [12]
All of the pararescuers and astronauts suffered from seasickness. Three hours after splashdown, Leonard F. Mason had both men and the spacecraft on board. The astronauts were exhausted, but had otherwise survived the flight and their time on the water in good condition. They were briefly checked and slept for nine hours.
The next morning, the ship docked at the port of Naha. Fellow astronaut Walter Schirra and other NASA officials flew in to greet them before the astronauts were summoned back to the ship for medical tests and debriefing. After release, they were brought by limousine to waiting helicopters where they flew to Kadena Air Base and then on to Florida on a C-135. [13]
Upon the return, the spacecraft was covered with a tarp. As part of the investigation into the mishap, ground controllers tested the Agena stage for the next several days by ordering it to perform various in-orbit maneuvers until exhausting its propellant and electrical power.
Four months later, the crew of Gemini 10 rendezvoused with the inert Agena and astronaut Michael Collins retrieved its micrometeorite collector.
No conclusive reason for the thruster malfunction was found. The most probable cause was determined to be an electrical short, most likely due to a static electricity discharge. Power still flowed to the thruster, even when it was switched off. To prevent recurrence of this problem, spacecraft designs were changed so each thruster would have an isolated circuit.
Quote from Flight: My Life in Mission Control by Chris Kraft, page 256:
Engineers tore into the OAMS system when the spacecraft got home and found a short circuit that made one thruster fire continuously. We learned an important lesson -never put electrical power to any system unless it’s supposed to be on. The OAMS was rewired so that a short circuit would always give us a dead thruster, not one that kept firing until a circuit breaker was opened by an astronaut.
The Deputy Administrator of NASA, Dr. Robert Seamans, was attending a celebratory dinner sponsored by the Goddard Space Flight Center, at which Vice President Hubert Humphrey was the guest speaker, when the problem arose. [14] The incident inspired Seamans to review NASA's problem investigation procedures, modeled after military crash investigations, and on April 14, 1966, to formalize a new procedure in Management Instruction 8621.1, Mission Failure Investigation Policy And Procedures. This gave the Deputy Administrator the option of performing independent investigations of major failures, beyond those failure investigations for which the various Program Office officials were normally responsible. It declared: "It is NASA policy to investigate and document the causes of all major mission failures which occur in the conduct of its space and aeronautical activities and to take appropriate corrective actions as a result of the findings and recommendations." [15] Seamans first invoked this new procedure immediately following the fatal Apollo 1 spacecraft fire on January 27, 1967. It was also invoked after the next critical in-flight failure, which occurred on the Apollo 13 lunar mission in April 1970.
McDonnell Aircraft Corporation, the Gemini spacecraft prime contractor, also changed its procedures. Prior to the accident, McDonnell's top engineers would be at Cape Kennedy Air Force Station for the launch, then fly to Mission Control in Houston, Texas for the rest of the mission. The problem occurred while they were en route, so it was decided to keep McDonnell engineers in Houston for the entire mission. [16]
The mission patch shows the whole spectrum of objectives that were hoped to have been accomplished on Gemini 8. The text at the bottom is composed of the zodiacal symbol for Gemini, , and the Roman numeral for eight, VIII. The two stars are Castor and Pollux, which are in the constellation of Gemini, and are refracted through a prism to provide the spectrum. Armstrong and Scott both designed the flight patch.
The Gemini 8 mission was dramatized in episode 1 "Can We Do This?", of the 1998 HBO miniseries From the Earth to the Moon , and in the 2018 Armstrong biopic, First Man . The story of the mission is told from the point of view of a fictional mission controller in the TV series For All Mankind (2021, Season 2, Episode 8).
Gemini 10 was a 1966 crewed spaceflight in NASA's Gemini program. It was the 8th crewed Gemini flight, the 16th crewed American flight, and the 24th spaceflight of all time. During the mission, flown by future STS-1 Commander John Young and future Apollo 11 Command Module Pilot Michael Collins, Collins became the first person to perform two extravehicular activities.
Project Mercury was the first human spaceflight program of the United States, running from 1958 through 1963. An early highlight of the Space Race, its goal was to put a man into Earth orbit and return him safely, ideally before the Soviet Union. Taken over from the US Air Force by the newly created civilian space agency NASA, it conducted 20 uncrewed developmental flights, and six successful flights by astronauts. The program, which took its name from Roman mythology, cost $2.68 billion. The astronauts were collectively known as the "Mercury Seven", and each spacecraft was given a name ending with a "7" by its pilot.
Gemini 3 was the first crewed mission in NASA's Project Gemini and was the first time two American astronauts flew together into space. On March 23, 1965, astronauts Gus Grissom and John Young flew three low Earth orbits in their spacecraft, which they nicknamed Molly Brown. It was the first U.S. mission in which the crew fired thrusters to change the size and shape of their orbit, a key test of spacecraft maneuverability vital for planned flights to the Moon. It was also the final crewed flight controlled from Cape Kennedy Air Force Station in Florida, before mission control functions were moved to a new control center at the newly opened Manned Spacecraft Center in Houston, Texas.
The Agena Target Vehicle, also known as Gemini-Agena Target Vehicle (GATV), was an uncrewed spacecraft used by NASA during its Gemini program to develop and practice orbital space rendezvous and docking techniques, and to perform large orbital changes, in preparation for the Apollo program lunar missions. The spacecraft was based on Lockheed Aircraft's Agena-D upper stage rocket, fitted with a docking target manufactured by McDonnell Aircraft. The name 'Agena' derived from the star Beta Centauri, also known as Agena. The combined spacecraft was a 26-foot (7.92 m)-long cylinder with a diameter of 5 feet (1.52 m), placed into low Earth orbit with the Atlas-Agena launch vehicle. It carried about 14,000 pounds (6,400 kg) of propellant and gas at launch, and had a gross mass at orbital insertion of about 7,200 pounds (3,300 kg).
John Watts Young was an American astronaut, naval officer and aviator, test pilot, and aeronautical engineer. He became the 9th person to walk on the Moon as commander of the Apollo 16 mission in 1972. He is the only astronaut to fly on four different classes of spacecraft: Gemini, the Apollo command and service module, the Apollo Lunar Module and the Space Shuttle.
David Randolph Scott is an American retired test pilot and NASA astronaut who was the seventh person to walk on the Moon. Selected as part of the third group of astronauts in 1963, Scott flew to space three times and commanded Apollo 15, the fourth lunar landing; he is one of four surviving Moon walkers and the only living commander of a spacecraft that landed on the Moon.
Gemini 4 was the second crewed spaceflight in NASA's Project Gemini, occurring in June 1965. It was the tenth crewed American spaceflight. Astronauts James McDivitt and Ed White circled the Earth 66 times in four days, making it the first US flight to approach the five-day flight of the Soviet Vostok 5. The highlight of the mission was the first space walk by an American, during which White floated free outside the spacecraft, tethered to it, for approximately 23 minutes.
Gemini 5 was a 1965 crewed spaceflight in NASA's Project Gemini. It was the third crewed Gemini flight, the eleventh crewed American spaceflight, and the nineteenth human spaceflight of all time. It was also the first time an American crewed space mission held the world record for duration, set on August 26, 1965, by breaking the Soviet Union's previous record set by Vostok 5 in 1963. This record might have been one day longer; however, Gemini V was cut short, due to the approach of Hurricane Betsy.
Gemini 7 was a 1965 crewed spaceflight in NASA's Gemini program. It was the fourth crewed Gemini flight, the twelfth crewed American spaceflight, and the twenty-first crewed spaceflight including Soviet flights and X-15 flights above the Kármán line. The crew of Frank Borman and Jim Lovell spent nearly 14 days in space, making a total of 206 orbits. Their spacecraft was the passive target for the first crewed space rendezvous performed by the crew of Gemini 6A.
Gemini 6A was a 1965 crewed United States spaceflight in NASA's Gemini program. The mission, flown by Wally Schirra and Thomas P. Stafford, achieved the first crewed rendezvous with another spacecraft, its sister Gemini 7. Although the Soviet Union had twice previously launched simultaneous pairs of Vostok spacecraft, these established radio contact with each other, but they had no ability to adjust their orbits in order to rendezvous and came no closer than several kilometers of each other, while the Gemini 6 and 7 spacecraft came as close as one foot (30 cm) and could have docked had they been so equipped.
Gemini 9A was a 1966 crewed spaceflight in NASA's Gemini program. It was the seventh crewed Gemini flight, the 15th crewed American flight and the 23rd spaceflight of all time. The original crew for Gemini 9, command pilot Elliot See and pilot Charles Bassett, were killed in a crash on February 28, 1966, while flying a T-38 jet trainer to the McDonnell Aircraft plant in St. Louis, Missouri to inspect their spacecraft. Their deaths promoted the backup crew, Thomas P. Stafford and Eugene Cernan, to the prime crew. The mission was renamed Gemini 9A after the original May 17 launch was scrubbed when the mission's Agena Target Vehicle was destroyed after a launch failure. The mission was flown June 3–6, 1966, after launch of the backup Augmented Target Docking Adaptor (ATDA). Stafford and Cernan rendezvoused with the ATDA, but were unable to dock with it because the nose fairing had failed to eject from the docking target due to a launch preparation error. Cernan performed a two-hour extravehicular activity, during which it was planned for him to demonstrate free flight in a self-contained rocket pack, the USAF Astronaut Maneuvering Unit. He was unable to accomplish this due to stress, fatigue, and overheating.
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Gemini 11 was the ninth crewed spaceflight mission of NASA's Project Gemini, which flew from September 12 to 15, 1966. It was the 17th crewed American flight and the 25th spaceflight to that time. Astronauts Charles "Pete" Conrad Jr. and Richard F. Gordon Jr. performed the first direct-ascent rendezvous with an Agena Target Vehicle, docking with it 1 hour 34 minutes after launch; used the Agena rocket engine to achieve a record high-apogee Earth orbit; and created a small amount of artificial gravity by spinning the two spacecraft connected by a tether. Gordon also performed two extra-vehicular activities for a total of 2 hours 41 minutes.
Gemini 12 was a 1966 crewed spaceflight in NASA's Project Gemini. It was the 10th and final crewed Gemini flight, the 18th crewed American spaceflight, and the 26th spaceflight of all time, including X-15 flights over 100 kilometers (54 nmi). Commanded by Gemini VII veteran James A. Lovell, the flight featured three periods of extravehicular activity (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.
Project Gemini was the second United States human spaceflight program to fly. Conducted after the first American crewed space program, Project Mercury, while the Apollo program was still in early development, Gemini was conceived in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual astronauts flew low Earth orbit (LEO) missions during 1965 and 1966.
A space rendezvous is a set of orbital maneuvers during which two spacecraft, one of which is often a space station, arrive at the same orbit and approach to a very close distance. Rendezvous requires a precise match of the orbital velocities and position vectors of the two spacecraft, allowing them to remain at a constant distance through orbital station-keeping. Rendezvous may or may not be followed by docking or berthing, procedures which bring the spacecraft into physical contact and create a link between them.
A space capsule is a spacecraft designed to transport cargo, scientific experiments, and/or astronauts to and from space. Capsules are distinguished from other spacecraft by the ability to survive reentry and return a payload to the Earth's surface from orbit or sub-orbit, and are distinguished from other types of recoverable spacecraft by their blunt shape, not having wings and often containing little fuel other than what is necessary for a safe return. Capsule-based crewed spacecraft such as Soyuz or Orion are often supported by a service or adapter module, and sometimes augmented with an extra module for extended space operations. Capsules make up the majority of crewed spacecraft designs, although one crewed spaceplane, the Space Shuttle, has flown in orbit.
The Orbit Attitude and Maneuvering System (OAMS) was a reaction control system used in Earth orbit by the Project Gemini spacecraft. It provided both automatic and manual rotation and translation by means of 16 vernier thrusters using hypergolic propellants.
The Atlas-Agena was an American expendable launch system derived from the SM-65 Atlas missile. It was a member of the Atlas family of rockets, and was launched 109 times between 1960 and 1978. It was used to launch the first five Mariner uncrewed probes to the planets Venus and Mars, and the Ranger and Lunar Orbiter uncrewed probes to the Moon. The upper stage was also used as an uncrewed orbital target vehicle for the Gemini crewed spacecraft to practice rendezvous and docking. However, the launch vehicle family was originally developed for the Air Force and most of its launches were classified DoD payloads.
Advanced Gemini is a number of proposals that would have extended the Gemini program by the addition of various missions, including crewed low Earth orbit, circumlunar and lunar landing missions. Gemini was the second crewed spaceflight program operated by NASA, and consisted of a two-seat spacecraft capable of maneuvering in orbit, docking with uncrewed spacecraft such as Agena Target Vehicles, and allowing the crew to perform tethered extra-vehicular activities.
This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration .