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: http://www.jsc.nasa.gov/history/flag/flag.htm
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International ConsiderationsPrior to the Apollo 11 moon landing, the United Nations (U.N.) adopted the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies of 27 January 1967 (commonly known as the Outer Space Treaty). Article II of the treaty clearly states that "outer space, including the moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of occupation, or by any other means." (footnote 3) The United States, signatory to the treaty, could not claim the moon. Therefore, raising a flag on the lunar surface would merely be a symbolic gesture -- an expression of triumph similar to the planting of a flag on Mount Everest or at the North and South Poles. The legal status of the moon clearly would not be affected by the presence of a U.S. flag on the surface, but NASA was aware of the international controversy that might occur as a result. (footnote 4)In January of 1969, President Richard M. Nixon's inaugural address stressed the international flavor of the Apollo program. "As we explore the reaches of space, let us go to the new worlds together -- not as new worlds to be conquered, but as a new adventure to be shared." NASA officials noted the tone of the speech, and there was some discussion within the agency that a United Nations flag could be used for the flight. (footnote 5) This was one of the possibilities considered by the Committee on Symbolic Activities for the First Lunar Landing, which was appointed by Thomas O. Paine, NASA Acting Administrator, on February 25 of that year. The committee was instructed to select symbolic activities that would not jeopardize crew safety or interfere with mission objectives; that would "signalize the first lunar landing as an historic forward step of all mankind that has been accomplished by the United States" and that would not give the impression that the United States was "taking possession of the moon" in violation of the Outer Space Treaty. The committee considered several options including the possibilities of leaving a United States flag or an adaptation of the solar wind experiment in the form of a flag, leaving a set of miniature flags of all nations, and leaving a commemorative marker on the surface. (footnote 6) The committee's report recommended using only the flag of the United States during the lunar extravehicular activity (EVA). In addition, the committee suggested that a plaque bearing an inscription ("Here men from the planet Earth first set foot upon the moon July 1969, A.D. We came in peace for all mankind") be mounted on the lunar module to emphasize that the purpose of the mission was one of exploration and not conquest. The original plaque design featured a U.S. flag, but the graphic was changed to pictures of the eastern and western hemispheres of the Earth to symbolize the crew's point of origin. It was decided that, in addition to the large flag, 4 x 6 inch flags of the 50 states, the District of Columbia, the U.S. territories, and flags for all member countries of the United Nations and several other nations, would be carried in the lunar module and returned for presentation to governors and heads of state after the flight. (footnote 7) Technical AspectsDesign and Engineering ConstraintsWork on the lunar flag assembly began about three months prior to the Apollo 11 mission. Robert Gilruth, Director of the Manned Spacecraft Center (MSC) (footnote 8) and a member of the Committee on Symbolic Activities, asked Jack Kinzler, Chief of Technical Services Division at MSC, for ideas regarding the EVA. Kinzler suggested that a full-size U.S. flag could be deployed using a specially designed flagpole. He drew up a preliminary sketch (Fig. 2) and the idea was presented to the committee. Working with Deputy Division Chief Dave McCraw, he worked out the details of the lunar flag assembly over several days. The design was based on a number of engineering constraints. For example, to compensate for the lack of an atmosphere on the lunar surface, the flag assembly included a horizontal crossbar to give the illusion of a flag flying in the breeze. (footnote 9)
Two other major constraints were the weight of the assembly and the stowage space required. The team designed the entire assembly to be as lightweight as possible -- when completed it weighed only 9 pounds and 7 ounces. They reduced the size of the package by developing a two-part telescoping pole apparatus with a telescoping crossbar. It was also necessary to design a flagpole that could be easily assembled and deployed by astronauts wearing space suits. Space suits used for the lunar surface EVA were pressurized to approximately 3.7 pounds per square inch and, as a result, the amount of force that the astronauts could apply with their gloved hands was limited and their range of movement was restricted (Fig. 3).
A 3 x 5 ft. nylon flag, obtained through the government supply catalog, (footnote 10) was altered by sewing a hem along the top. The crossbar, hinged to the pole, went through this hem, and a loop sewn around the bottom of the flag secured it to the pole. An astronaut would unfurl the flag by extending the telescoping crossbar and by raising it first to a position just above 90 degrees. He then lowered it to a position perpendicular to the pole where a catch prevented the hinge from moving. The upper portion then slipped into the base portion of the flagpole, which had been driven into the ground using a lunar geological hammer. A red ring was painted around the base of the assembly 18 inches from the bottom to aid the astronauts in judging the distance that the pole had penetrated the surface. (footnote 11) Finally, it was necessary to protect the flag during the descent portion of the lunar landing. To make the flag easily accessible during the EVA, it was mounted on the left-hand side of the ladder on the Lunar Module (LM) (fig. 4). This also reduced the amount of equipment that had to carried inside the already crowded vehicle. It was estimated, however, that the LM ladder would be heated to 250 degrees Farenheit by the descent engines as they fired during the descent staging phase of the landing. The ladder would experience temperatures up to 2,000 degrees Farenheit during the 13 seconds of the touchdown phase. Tests run on the flag determined that it would withstand temperatures of only up to 300 degrees Farenheit . These conditions made it necessary to design a protective shroud for the flagassembly. The shroud design (Fig. 5) was the work of the Structures and Mechanics Division of the Manned Spacecraft Center. It consisted of a stainless steel outer case separated from an aluminum layer by Thermoflex insulation. Several layers of thermal blanketing material were placed between the shroud and the flag assembly, limiting the temperature experienced by the flag to 180 degrees Farenheit . (footnote 12)
Construction and TestingAll of the work on the flag assembly and on the flag shroud was performed in the workshops at the Manned Spacecraft Center. Alterations to the flag were done in the fabrics shop, the sheet metals shop constructed the flagpole, and another shop anodized the flagpole -- electrolytically coating the aluminum to give it a gold color and a stiff protective surface. Tubing used in the construction of the pole was about an inch in diameter with a wall approximately 1/32 of an inch thick. The telescoping feature of the pole was created by using different sizes of tubing that slid neatly into each other. A capped bottom allowed the upper portion of the pole to slide easily into the lower portion. The base of the lower section was designed with a hardened steel point to make it easier to drive into the lunar soil.Cost of materials was relatively low -- the flag was purchased for $5.50 and the tubing cost approximately $75. The cost of the shroud has been estimated at several hundred dollars due to the materials involved. Construction of the prototypes was achieved in several days, and after a week the team had made a few backup assemblies, and some to be used for crew training purposes. Demonstration tests were performed where the flag assembly was folded, packed, unpacked, erected and deployed to assure that it would operate properly. Kinzler flew to Kennedy Space Center in Florida to participate in a mockup review of the lunar flag assembly on 25 June 1969. The astronauts were included in several of these tests as part of their EVA training so that they would be familiar with deployment procedures. (footnote 13) Preflight PreparationPacking of the flag assembly followed a written 12-step procedure which required up to 5 people to ensure that it was tightly packed. Wooden blocks and plastic ties were used by the team to keep the packed flag together as they progressed through the steps. These packing aids were removed when the flag was placed into the thermal package. After the flag was rolled into the thermal package a thermal rip strip made with Velcro was used to close the package. The strip had a pull-tab at the top to make it easier for the astronauts to open the package once they were on the lunar surface. This thermal package was then installed into the metal shroud following a 4-step procedure. A small block of Thermaflex insulation was placed around the bottom and top ends of the pole to protect the flag ends from hot brackets. The flag packing for the Apollo 11 flight was performed in Jack Kinzler's office and was approved by the Chief of Quality Assurance who was present during the procedure. Once the flag thermal package was properly stowed inside the shroud, it was taken to the launch site at KSC to be mounted on the ladder of the LM. (footnote 14)Because the final decision to fly the flag and attach the plaque was made so close to the launch date, a Lear jet was chartered to fly Kinzler, George Low (Manager of the Apollo Spacecraft Program), Low's secretary, the flag assembly, and the commemorative plaque to KSC before the launch. The flag and plaque were installed on the LM of Apollo 11 at 4:00 in the morning as the spacecraft sat atop its Saturn V rocket ready for launch. Kinzler had written an 11-step procedure for mounting the assembly on the ladder and personally supervised the installation. Proper installation was vital if the astronauts were to be able to deploy the flag on the lunar surface. An astronaut first released the shroud "pip" pin by squeezing it and then pulling it out, and then released the main flag assembly "pip" pin. A spring tension against the flag poles was released when the pins were pulled allowing easy removal of the shroud. The astronaut then pulled the Velcro strip off the insulation package and discarded the wrapping materials. Deployment and PerformanceThe first U.S. flag on the moon was deployed by Neil Armstrong and Edwin "Buzz" Aldrin during their historic EVA on 20 July 1969 (at 4 days, 14 hours and 9 minutes mission-elapsed time). The flag was seen worldwide on live television (Fig. 6). At their technical crew debriefing, Armstrong and Aldrin reported few problems with the deployment. They had trouble extending the horizontal telescoping rod and could not pull it all the way out. This gave the flag a bit of a "ripple effect," and later crews intentionally left the rod partially retracted. The Apollo 11 astronauts also noted that they could drive the lower portion of the pole only about 6 to 9 inches into the surface. It is uncertain if the flag remained standing or was blown over by the engine blast when the ascent module took off.
The only design change made as the result of performance on the lunar surface was in the catching mechanism of the horizontal crossbar's hinge. The Apollo 12 crew could not get the catch to latch properly and, as a result, the flag drooped slightly. Later models of the flag assembly had a double-action latch that would work even if the horizontal bar was not raised above a 90 degree angle. (footnote 15) Reactions to the Flag DeploymentEven though the event took only 10 minutes of the 2 1/2 hour EVA, for many people around the world the flag-raising was one of the most memorable parts of the Apollo 11 lunar landing. There were no formal protests from other nations that the flag-raising constituted an illegal attempt to claim the moon. Buzz Aldrin, in an article written for Life magazine, stated that as he looked at the flag he sensed an "almost mystical unification of all people in the world at that moment." A few published articles expressed regret that NASA had chosen not to plant a U.N. flag, either in addition to or alongside that of the United States.Prior to the mission, several members of Congress relayed letters from their constituents to NASA which recommended (or in some cases opposed) the use of specific flags. Flags mentioned in these letters included the U.S. flag, the U.N. flag, |