Gemini 7

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Gemini VII

Gemini 7 as seen by Gemini 6
Operator NASA
COSPAR ID 1965-100A
SATCAT № 1812
Mission duration 13 days, 18 hours, 35 minutes, 1 second
Distance travelled 9,030,000 kilometres (4,876,000 nautical miles)
Orbits completed 206
Spacecraft properties
Spacecraft Gemini SC7
Manufacturer McDonnell
Launch mass 3,670 kilograms (8,080 lb)
Crew
Crew size 2
Members Frank F. Borman, II
James A. Lovell, Jr
Start of mission
Launch date December 4, 1965, 19:30:03 (1965-12-04UTC19:30:03Z) UTC
Rocket Titan II GLV, s/n 62-12562
Launch site Cape Canaveral LC-19
End of mission
Landing date December 18, 1965, 14:05:04 (1965-12-18UTC14:05:05Z) UTC
Landing site 25°25.1′N 70°6.7′W / 25.4183°N 70.1117°W / 25.4183; -70.1117 (Gemini 7 splashdown)
Orbital parameters
Reference system Geocentric
Regime Low Earth
Perigee 161.7 kilometres (87.3 nautical miles)
Apogee 217.1 kilometres (117.2 nautical miles)
Inclination 28.89 degrees
Period 89.39 minutes


(L-R) Lovell, Borman


Project Gemini
 Gemini 5 Gemini 6A

Gemini 7 (officially Gemini VII)[1] was a 1965 manned spaceflight in NASA's Gemini program. It was the 4th manned Gemini flight, the 12th manned American flight and the 20th spaceflight of all time (includes X-15 flights over 100 kilometers (330,000 ft)). The crew of Frank F. Borman, II and James A. Lovell, Jr spent nearly 14 days in space making a total of 206 orbits, and were joined on orbit by the Gemini-6A flight which performed the first rendezvous maneuver of manned spacecraft.

Crew

Position Astronaut
Command Pilot Frank F. Borman, II
First spaceflight
Pilot James A. Lovell, Jr
First spaceflight

Backup crew

Position Astronaut
Command Pilot Edward H. White, II
Pilot Michael Collins

Support crew

Mission parameters

  • Mass: 8,080 pounds (3,670 kg)
  • Perigee: 87.3 nautical miles (161.7 km)
  • Apogee: 177.2 nautical miles (328.2 km)
  • Inclination: 28.89°
  • Period: 89.39 min

Stationkeeping with GT-6A

  • Start: December 15, 1965 19:33 UTC
  • End: December 16, 1965 00:52 UTC
  • Gemini 6 and 7

Objectives

Lovell before the launch, in the special G5C space suit, which had a zippered hood with a visor instead of a solid helmet.

Gemini 7 was originally intended to fly after Gemini 6, but the original Gemini 6 mission was cancelled after the failure during launch of the Agena Target Vehicle with which it was meant to rendezvous and dock. The objective of rendezvous was so important, that it was decided to fly Gemini 6 at the same time as Gemini 7, using the latter as the rendezvous target.

The original mission of Gemini 7 changed little with these new plans. It was always planned to be a long duration flight, investigating the effects of fourteen days in space on the human body. This doubled the length of time that anyone had been in space and stood as the longest spaceflight duration record for five years.

This 14 day mission required NASA to solve problems of long-duration space flight, not the least of which was stowage (the crew had practiced stuffing waste paper behind their seats before the flight). Timing their workday to match that of ground crews, both men worked and slept at the same time. Gemini VII flew the most experiments 20 of any Gemini mission, including studies of nutrition in space. The astronauts also evaluated a new lightweight spacesuit, which proved uncomfortable if worn for a long time in Gemini's hot, cramped quarters. The high point of the mission was the rendezvous with Gemini VI. But the three days that followed were something of an endurance test, and both astronauts, heeding Pete Conrad's Gemini V advice, brought books along. Gemini VII was the longest space flight in U.S. history until the Skylab missions of the 1970s.

Flight

The launch and ascent were nominal. After separating from the spent rocket stage, they turned the spacecraft around and proceeded to station keep with the rocket stage, a maneuver first tried on Gemini 4. The Gemini 4 attempt was unsuccessful, due to the limited knowledge at the time of the complex orbital mechanics involved. Gemini 7 flew in formation with its upper stage for fifteen minutes, at which time Borman stopped because he felt too much fuel was being consumed, and the stage was moving erratically as it vented its own remaining fuel.

They spent the rest of their first day in space doing some experiments and eating their first meal. Their sleep periods were scheduled at the same time unlike previous missions and they were able to get some sleep. The next morning they woke at 9:06 am EST and found out the day's news which included the fact that two airliners had collided over New York. For the first time during a flight, one of the crew was allowed to take off his suit. Borman and Lovell had planned to both take them off two days into the mission when they were satisfied that the environmental system was working properly. The NASA managers did not like this idea and said that at least one crew member had to be wearing a suit at all times. Borman was wearing his suit and was sweating profusely, but agreed to let Lovell stay out his suit as Lovell was the larger of the two and it required a lot of effort to get in and out of a suit in little more space than the front seat of a car.

Moon and clouds over the Western Pacific as seen from Gemini 7 spacecraft

Later the flight controllers ordered Lovell to don his suit and Borman to get out of his. This was because the doctors wanted to see the effects of being suited and unsuited on the crewmembers. So 148 hours into the flight, Borman got his chance to cool down. Finally the NASA managers decided that there was little benefit in having the crew members suited and so relented after a couple of days.

After five days, they had performed four orbital adjustment burns that put them in a circular 162-nautical-mile (300 km) orbit. This meant that the Gemini 7 spacecraft could stay in orbit for at least 100 days without its orbit degrading, more than stable enough for the passive target during a space rendezvous.

On their 31st orbit Gemini 7 observed the underwater launch and exhaust trail of a Polaris Missile from the submarine USS Benjamin Franklin off Florida.

Rendezvous

Gemini 6A launched December 15, after a three-day-long delay due to a malfunction and engine shutdown immediately after ignition. It entered into an 87-by-140-nautical-mile (161 by 259 km) orbit, and was briefly visible from Gemini 7 just after launch. Borman and Lovell were also able to see the contrail from the launch.

The plan called for the rendezvous to take place on the fourth orbit of Gemini 6A. Their first burn came 94 minutes after launch when they increased their velocity by 16.5 ft/s (5.0 m/s). Due to their lower orbit they were gaining on Gemini 7 and were 634 nautical miles (1,174 km) behind. The next burn was at 2 hours and 18 minutes when Gemini 6A made a phase adjustment to put them on the same orbital inclination as Gemini 7. They now only trailed by 261 nautical miles (483 km).

The radar on Gemini 6A first made contact with Gemini 7 at 3 hours and 15 minutes when they were 234 nautical miles (433 km) away. A third burn put them into a 146-by-148-nautical-mile (270 by 274 km) orbit. As they slowly gained, Walter Schirra put Gemini 6A's computer in charge of the rendezvous, and at 5 hours and 4 minutes, he saw a bright object that he at first thought was the star Sirius, but was in fact Gemini 7.

After several more burns the two spacecraft were only 130 feet (40 m) apart. The burns had only used 110 pounds (50 kg) of fuel on Gemini 6A, leaving plenty of fuel. During the next 270 minutes the crews moved as close as 1 foot (30 cm), talking over the radio. At one stage the spacecraft were station-keeping so well that neither crew had to make any burns for 20 minutes.

As the sleep periods approached, Gemini 6A made a separation burn and slowly drifted out to 16 kilometers, to prevent an accidental collision in the night. Gemini 6A reentered the next day, landing within 9.7 nautical miles (18.0 km) of the planned site, the first truly accurate atmospheric reentry.

Last few days

By this time the novelty of spaceflight had worn off for the crew of Gemini 7. They had spent 11 days in space and had three more to go. They were doing little more than drifting around the Earth and the incentive of the rendezvous was over. Borman read Roughing It by Mark Twain and Lovell Drums along the Mohawk by Walter D. Edmonds. Malfunctions began: some of the thrusters stopped working. After the flight this was traced to the fact that they had an old type of laminate in the thrust chamber. Also on the 12th day the fuel cells started to give only a partial amount of power. But the manufacturers of the Gemini spacecraft decided that the spacecraft could survive by battery power alone for the next couple of days.

Finally the last day of the mission arrived and the crew stored everything for re-entry. The retro-rockets worked perfectly after 14 days in space. They landed within 6.4 nautical miles (11.9 km) of the targeted landing point.

The crewmen were somewhat weakened by their time in space, but both were in good health and were up and about after a good night's sleep on the recovery ship USS Wasp. They were also in good spirits: during recovery, they joked to Mission Control about getting married after having spent so long together in space.

The Gemini 7 and 6-A missions were supported by the following U.S. Department of Defense resources: 10,125 personnel, 125 aircraft and 16 ships.

Insignia

The patch features an Olympic torch, symbolizing the marathon-like length of the mission. There is a small stylized image of a Gemini spacecraft and the roman numerals VII for seven. The crew did not put its names on the patch, although souvenir versions did include the flight and crew names. The crew patch was designed by Houston artist and animator Bill Bradley.[2][3]

As with a few other missions, the backup crew produced a spoof of the insignia, featuring an unlit torch, a lighter and the words "NEED A LIGHT - FRANK? JIM?"

Spacecraft location

Gemini 7 spacecraft on display at the Steven F. Udvar-Hazy Center

The spacecraft is on display at the Steven F. Udvar-Hazy Center, Chantilly, Virginia.

See also

References

 This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.

  1. Hacker, Barton C.; Grimwood, James M. (September 1974). "Chapter 11 Pillars of Confidence". On the Shoulders of Titans: A History of Project Gemini. NASA History Series. SP-4203. NASA. p. 239.  With Gemini IV, NASA changed to Roman numerals for Gemini mission designations.
  2. Bradley, William. "History of Bradley's Art and Frame Shop, Houston, TX". Retrieved 2011-12-15. 
  3. "Bradley's Art & Frame shop newsletter". NASA Patches. 

External links

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