Gemini 7

Infobox Space mission
mission_name = Gemini 7
spacecraft_name = Gemini 7
booster = Titan II #62-12562
insignia = Ge07Patch orig.png insignia_size = 162px
sign = Gemini 7
crew_members = 2
launch_pad = LC-19 (CCAF)
launch = December 4, 1965, 19:30:03 UTC
landing = December 18, 1965, 14:05:04 UTC coord|25|25.1|N|70|6.7|W
duration = 13d/18:35:01
orbits = 206
apogee = convert|328.2|km|nmi|lk=on
perigee = convert|161.6|km|nmi
period = 89.39 min.
inclination = 28.89°
distance = convert|9029771|km|mi|lk=on
mass = convert|3663|kg|lb|lk=on
crew_photo = Gemini 7 Crew (Lovell und Borman).jpg
crew_caption = (L-R) Lovell, Borman
previous =
next =

Gemini 7 (officially Gemini VII) 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 km).

Crew

Number in parentheses indicates number of spaceflights by each individual prior to and including this mission.
* Frank F. Borman, II (1) - Command Pilot
* James A. Lovell, Jr (1) - Pilot

Backup crew

* Edward H. White, II (1) - Command Pilot
* Michael Collins - Pilot

Mission parameters

* Mass: 3,663 kg
* Perigee: 161.6 km
* Apogee: 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

ee also

* Splashdown

Objectives

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. However the objective of rendezvous was so important it was decided to fly Gemini 6 at the same time as Gemini 7, using the latter as the rendezvous target.

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.

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 a fortnight in space on the human body. The nearly fourteen days in space would double the length of time that anyone had been in space and would stand as the single longest spaceflight duration record for five years.

Flight

Their launch and ascent was nominal. After separating from the spent rocket stage, they turned the spacecraft around and proceeded to station keep with the rocket stage. They spent fifteen minutes formation flying with the stage, but Borman felt they were using too much fuel and the rocket stage was acting erratically as it vented its own 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 days news which included the fact that two airliners had collided over New York. [http://aviation-safety.net/database/1965/651204-1.htm] For the first time during a flight, one of the crew were allowed to take off their suits. 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 didn't like this idea and said that at least one crew member had to be wearing his suit at all times. Borman who was wearing his suit 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.

In the end, 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. In the end, 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 300 kilometer 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.

Rendezvous

Gemini 6A launched December 15, after a day-long delay due to a malfunction right at the point of ignition. It entered into a 161 by 259 kilometer 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 speed by 5 meters per second. Due to their lower orbit they were gaining on Gemini 7 and were only 1,175 kilometres 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 483 kilometers.

The radar on Gemini 6A first made contact with Gemini 7 at 3 hours and 15 minutes when they were 434 kilometers away. A third burn put them into a 270 by 274 kilometer orbit. As they slowly gained Walter Schirra put Gemini 6A's computer in charge of the rendezvous and then at 5 hours and 4 minutes he saw a bright star that he thought was Sirius, but was in fact Gemini 7.

After several more burns the two spacecraft were only 40 meters apart. The burns had only used 51 kilograms of fuel on Gemini 6A, giving plenty of fuel for some fly arounds. During the next 270 minutes the crews moved as close as 30 centimeters, talking over the radio. At one stage the spacecraft were stationkeeping 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 18 km of the planned site, the first truly accurate reentry.

The 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 already and had three more to go. They were doing little more than drifting around the Earth and the incentive of the rendezvous had gone. Borman read "Roughing It" by Mark Twain and Lovell "Drums along the Mohawk" by Walter D. Edmonds.

Malfunctions began to start. 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 cell 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 stowed everything for re-entry. The retro-rockets worked perfectly, even after 14 days in space. They managed to land within 11.8 kilometres of the targeted landing point.

The crew were somewhat weakened by their time in space. However, 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 & 6A 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.

As with some other missions, the backup crew did a spoof of the patch, featuring an unlit torch, a lighter and the words "FRANK-JIM ... GOT A LIGHT?"

Capsule location

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

External links

* [http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790076811_1979076811.pdf Gemini 7 Mission Report (PDF) January 1966]
* On The Shoulders of Titans: A History of Project Gemini: http://www.hq.nasa.gov/office/pao/History/SP-4203/cover.htm
* Spaceflight Mission Patches: http://www.genedorr.com/patches/Intro.html