Читать книгу Man on the Moon: A Picture Chronology of Man in Space Exploration - Anonymous - Страница 4
ОглавлениеHOW IT BEGAN
APOLLO 11 ON PAD 39A
The Apollo Program was designed to be the follow-on to the first manned satellite program of the U.S.
The National Aeronautics and Space Administration was established October 1, 1958, almost one year after the launching of Sputnik I by the Soviet Union. Within a week the United States’ first manned space program, later designated Project Mercury, was approved. The goal of this program was to develop the management and technological know-how necessary to put a man in space in earth orbit in order to establish man’s ability to survive and function in the heretofore unknown environment of space.
The Mercury objectives were accomplished during a program which included 19 unmanned and six manned missions. Mercury provided the United States with the beginnings of a competence in manned space flight as well as with an industrial base, ground facilities, and operational experience required for more advanced and complex space exploration.
Most of the emphasis in NASA was placed on the Mercury Project until the announcement of plans for Apollo was made at NASA Headquarters in Washington, D. C., on July 29, 1960.
At that time only one broad objective was stated for the manned space flight program: To provide the capability for manned exploration of space.
As envisioned, the advanced spacecraft program, Apollo, would be designed to allow man to perform useful functions in space. This spacecraft “should be capable of manned circumlunar flight as a logical intermediate step toward future goals of landing men on the moon and other planets.”
Difficulty of Goal
After Apollo was selected as an advanced manned program, a number of studies were conducted to determine the feasibility of various types of missions as well as different modes of accomplishing lunar landing.
Three primary methods for achieving the lunar landing mission were: (1) direct flight of a full-size space vehicle from earth to the moon and return; (2) launching separate major components into earth orbit, assembling them, and sending them as a single space vehicle to land on and take off from the moon; and (3) launching the whole spacecraft from earth to lunar orbit and landing a module on the lunar surface while the rest of the spacecraft remains in lunar orbit waiting for the lunar module to return and dock.
Finally, in July 1962, the third method, called lunar orbit rendezvous, was chosen after much time was spent in exhaustive study of the advantages and disadvantages of each of the proposed methods.
In the meantime, President John F. Kennedy challenged the Congress and the country to support a manned space program which would result in the United States landing a man on the moon and returning him safely to earth before 1970. This challenge, stated to the Congress in a personal appearance by the President on May 25, 1961, was accepted.
The difficulty of the goal to be achieved can only be understood when it is realized that at that time none of the basic essentials for such an accomplishment were available. No contractor had been selected to develop and build the spacecraft, the launch vehicle for the mission had not yet been selected or built, and, as mentioned before, the method of attaining the goal had not been determined. In addition, required facilities such as were necessary for launching and mission control were not in existence or in the planning stage.
Besides all this, Apollo was to be the largest and most complex technological program ever attempted by the United States or any other nation and required that management and manufacturing techniques be reevaluated and improved as necessary to carry out the tremendous research effort.
Many of these requirements were subsequently accomplished during the Gemini Program, which sent a series of two-man spacecraft into earth orbit during 1965 and 1966. However, the Gemini Program did not come into being until January 3, 1962, a year and a half after Apollo was initiated, when the need for an intermediate program to bridge the gap between the Mercury and Apollo programs was recognized.
THE MILKY WAY GALAXY
ORBITS OF THE PLANETS
THE EARTH AND MOON
RELATIVE SIZES OF PLANETS AND APPROXIMATE DISTANCES FROM THE SUN
THE SOLAR SYSTEM
AS SEEN LOOKING TOWARD EARTH FROM THE MOON
SPACECRAFT
MERCURY • GEMINI • APOLLO
GEMINI VII SPACECRAFT FROM GEMINI 7/6 RENDEZVOUS
December 15, 1965
The required spacecraft was successively more complex as the manned spaceflight program progressed. For instance, in the Mercury spacecraft there were seven miles of wiring, in the Gemini spacecraft ten and a half miles, and in the Apollo command module alone there are fifteen miles of wiring. Additionally, the Mercury spacecraft consisted of 750,000 parts, the Gemini spacecraft of 1,320,000, and the command module of the Apollo by itself has about 2,000,000 functional parts.
The objectives of the Gemini Program, accomplished with striking success in two unmanned and ten manned Gemini spaceflights, were:
To subject two men and supporting equipment to long duration flights—a requirement for projected later trips to the moon or deeper space.
To effect rendezvous and docking with other orbiting vehicles; and to maneuver the docked vehicles in space, using the propulsion system of the target vehicle for post-docking maneuvers.
To perfect methods of reentry and landing the spacecraft at a preselected point. Land-landing was dropped as an objective during the early conduct of the Gemini Program.
To gain additional information concerning the effects of weightlessness on crew members and to record physiological and psychological reactions of crew members during long duration flights.
To develop capability for extravehicular activity by astronauts.
To attain flight and ground crew proficiency.
To conduct scientific experiments.
These objectives were successfully attained and the Gemini flight program was concluded with the landing and recovery of the Gemini XII spacecraft on November 15, 1966.
Great contributions to the manned lunar landing have also been made by the unmanned scientific programs, particularly the Ranger, Lunar Orbiter, and Surveyor programs, in which tens of thousands of photographs were taken of almost the entire surface of the Moon, indicating several likely landing sites for the Apollo astronauts. The unmanned Surveyor spacecraft, after soft landings on the Moon, each made a chemical analysis of the lunar soil. From the data thus obtained, it was determined that the lunar soil at the locations of those landings consists principally of basalt, the type of volcanic rock found on large areas of the earth, and contains traces of magnesium, aluminum, nickel, and other minerals. The data also revealed the presence of magnetic iron on the moon’s surface. Oxygen and silicon were shown to be the most common elements, as is true of the earth, and it was confirmed that the lunar surface is firm and could support the landing vehicle with no difficulty.
