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After Apollo, What?

Rudy Abramson covered the space program for the Los Angeles Times and wrote this piece examining the next possible steps in American manned spaceflight for the 1970 Britannica Book of the Year.

During the 1960s the widely publicized national commitment to put an American on the moon before the end of the decade, and also before the Soviet Union did so, gave the United States’ space program such urgency and purpose that Congress was moved to appropriate, in peak years, more than $5 billion for the U.S. National Aeronautics and Space Administration (NASA). But as the manned space effort entered the 1970s, it was under relentless reassessment. The increasingly asked question was where should space rank in the scheme of national priorities. The answer was clear. Space exploration, as a national activity, was regarded as far less important than it had been a few years before.

By the time of Apollo 11‘s spectacular fulfillment of the lunar landing goal, the social problems of the U.S. were being pressed upon the public conscience as never before; there was a nationwide quest to improve the quality of life. Inflation had become the country’s most persistent headache, aside from the war in Vietnam itself, and there was a seemingly sudden public conviction that environmental pollution was a national disgrace.

In this new atmosphere, it was seriously questioned whether the manned space program—the country’s most celebrated single undertaking of the 1960s—was squandering limited technological talent and resources. Congress, exerting its authority more than it had in many years, began taking a tougher attitude toward nearly all high-cost engineering development programs—even those said to be vital to the national defense. Instead of justifying manned space flight as an unavoidable area of competition with the Soviet Union, public officials talked more seriously of substantive cooperation with the U.S.S.R., thus endorsing the idea of making space exploration an international pursuit.

By fiscal 1971—beginning July 1, 1970—NASA’s budget had been reduced to a little more than $3 billion. Project Apollo was nearing its end; unmanned space projects were being postponed; both government and industry payrolls associated with space projects were being reduced.

The once-held dream of some officials to follow up the Apollo moon program with a similar commitment to land men on Mars had long since evaporated. A new blueprint, altogether different from the space plan of the 1960s, had solidified a year after the first moon landing. There would be no single objective like the moon landing deadline. The goal of the new approach was to develop a broad capability that could be used for practical returns: such a capability would embrace scientific research in earth orbit, and continued exploration of the moon and beyond.

Although disagreement remained over how fast the manned space program should progress and how much the U.S. could afford to spend, the general direction for the 1970s appeared to be charted. Envisioned was a new family of space transportation vehicles, designed for repeated use: a shuttle craft to operate routinely between the ground and low earth orbit; a so-called “space tug” to move such heavy objects as space stations or scientific observatories from one orbit to another or to haul cargo between the surface of the moon and a space station in lunar orbit; and a nuclear-powered shuttle for long-distance moving, such as sending a space station from earth orbit to lunar orbit, or starting a scientific payload on its way to neighbouring planets from earth orbit.

Development of the earth-to-orbit shuttle—which would also be used by the U.S. Air Force—emerged in 1970 as the first key step in developing the new post-Apollo manned space program. Close behind the shuttle in NASA’s plans was a permanent space station capable of supporting a dozen or more scientists and engineers in earth orbit.

Skylab

But the slowdown in space spending has already produced a gap between the end of the Apollo moon flights and the first orbital missions of the shuttle. The bridge between these two generations is a program called Skylab. A forerunner of the permanent space station, Skylab will consist of the third stage of a Saturn V moon rocket converted into an earth orbital workshop where teams of three astronauts will work for periods up to 56 days. Carrying scientific experiments in the fields of astronomy, space physics, biology, oceanography, water management, agriculture, forestry, geology, geography, and ecology, Skylab is scheduled for launch in late 1972.

The workshop will be divided into two “stories,” with living quarters and recreational facilities for the astronauts apart from the laboratory work area. Mounted outside the vehicle will be a solar telescope, which the astronauts will use to study portions of the sun’s electromagnetic spectrum not visible to earthbound observatories. With the workshop, telescope equipment, and docking hardware, Skylab will stretch 117 ft. in length and have a wingspan of 90 ft. after its massive solar panels unfold to convert the sun’s energy into electricity for the station.

During a lifetime of about eight months, Skylab will be used by three different astronaut teams. A day after a Saturn V lofts the workshop into an orbit about 270 nautical miles high, three astronauts, in an Apollo command module, will be launched by a smaller Saturn I booster. Afterward, they will rendezvous and dock with the workshop. Then, in a comfortable “shirt-sleeve” environment, these first visitors will live in Skylab for 28 days before returning to earth. This 28-day mission will break the previous endurance record of 17 2/3 days set by two Soviet cosmonauts in 1970. About two months later, a second team will fly to the laboratory for a mission lasting 56 days. A 56-day visit by the third crew will begin about a month after the second team has descended in its Apollo spacecraft.

A prime objective of the three flights is to find whether there are still unsuspected hazards in prolonged exposure to weightlessness. Through Skylab, the information will be available soon enough to use in the design of the permanent space station. If surprising physiological problems do arise from long-term weightlessness, then it might be necessary to design a permanent station that will be in constant rotation so as to produce artificial gravity.

Medical and physiological experiments will be assigned top priority on the first Skylab visit. The second crew will have solar astronomy as its number one assignment. The third will emphasize earth resources work, and will use instruments aboard the laboratory—mainly cameras—to see how well orbital observatories, manned or unmanned, can detect natural resources, identify crop diseases, and aid planners in land management.

Skylab is to be launched at a greater inclination to the Equator than any previous U.S. manned space vehicle. As a result, its earth resources cameras will be able to cover any area of the United States and most of the most heavily populated regions of the entire earth. U.S. astronauts had previously passed over the United States along a path cutting across southern California, Texas, the Gulf of Mexico, and Florida.

Because a backup Skylab is being assembled against the possibility of losing the first in a launch failure, NASA might have the opportunity of orbiting a second workshop. The first—including the cost of the backup—is expected to cost approximately $2 billion. Depending on how many changes are made, a second Skylab could be flown at a relatively low cost. A decision as to whether to fly the second workshop is expected in the summer or fall of 1971.

Apollo Cutback

Whether or not a second Skylab is launched, it would not be able to span the gap completely between Apollo and the new programs. As the budget pinch began, NASA had already dropped one of its planned moon landings. It also decided to convert a Saturn V third stage into Skylab before launch, rather than using Saturn Is and outfitting an expended upper stage as a crude workshop after it had reached orbit.

As the financial pressure became more intense, NASA decided to cut further into Apollo to keep the plans for the shuttle and space station alive. It speeded the layoff of space contractor employees and decided to mothball rocket test facilities in Mississippi and to suspend production of the Saturn V.

An earlier plan had been to fly Apollo missions through 17 and then take a year’s break from exploring the moon to conduct the Skylab before concluding the Apollo program with two flights in 1974. But a cutback of two flights by NASA meant that there would be two flights to the moon in 1971, two in 1972, and then Skylab, which would be completed in June 1973. After that, the U.S. would have no manned space activity until the shuttle was ready in 1976 or 1977—unless there was a decision to fly a second Skylab. By cutting the number of moon flights, NASA officials expected that they would be able to save a total of $600 million to $900 million for work on the shuttle and space station.

Both of the scientific advisory panels consulted on the decision urged NASA to go ahead and fly its lunar missions through Apollo 19. Instead of cutting back exploration of the moon, they argued, the Skylab program should be postponed.

In a letter to NASA Administrator Thomas O. Paine, Nobel laureate Charles H. Townes, chairman of the Space Science Board, and John W. Findlay, chairman of the Lunar and Planetary Missions Board, explained the reasoning of the scientific community:

It should be recognized that any reduction in the number of missions will seriously threaten the ability of the total Apollo program to answer first-order scientific questions. We are concerned that a further reduction in the present Apollo may well lead to our inability to answer these questions and that the consequences of such failure for the future of the agency and, we believe, for large-scale science in this country, are incalculable.

Shuttle Program

The shuttle program NASA hopes to get approved in Congress in 1971 could cost, by the agency’s own estimates, more than $6 billion. Some skeptics put the figure much higher than that. But in spite of this cost the prime motive behind the shuttle concept is to reduce for all time the cost of sending men and equipment into orbit. It may be able to reduce Saturn V’s freight rate of $1,000 per pound to $20 to $50 per pound; besides that, it will be able to haul cargo from space down to earth, which conventional rockets cannot do because they are lost after launch.

Designers are aiming for a shuttle that will operate much in the fashion of a commercial airliner. It must be capable of being readied for launch in a period of two hours and must be able to make at least 100 round trips from earth to orbit without major refurbishment.

The shuttle NASA wants to build consists of two vehicles—a booster and an orbiter. Launched vertically like other rockets, the booster will carry the smaller orbiter piggyback-style to an altitude of about 200,000 ft., where they will separate. The booster will descend and, powered by jet engines, fly back to the launch base under control of a two-man crew. The orbiter will then continue on to an altitude of 100 mi. or more.

Though the orbiter will be much smaller than the powerful booster that pushes it off the ground, it will be about the size of a Boeing 707 jetliner. NASA has told contractors working on preliminary design that the shuttle must have a cargo compartment 15 ft. in diameter and 60 ft. in length. A shuttle of these dimensions will be able to carry as many as a dozen passengers and make the transit to and from orbit gently enough for middle-aged scientists to make the trip as comfortably as professional astronauts. Returning from orbit, it will land at the same base where it took off, touching down on an ordinary runway.

Capable of operating at altitudes up to 600 nautical miles, the shuttle will have a payload up to 50,000 lb. Since it will be used by the U.S. Air Force as well as NASA, its design will probably be somewhat influenced by military requirements. As preliminary design studies progressed, the space agency and the Air Force disagreed about whether the orbiter should have fixed wings or be delta-shaped to give it increased maneuverability on reentry, as the Air Force wanted.

While the shuttle is basically a transportation system to ferry satellites and carry men and supplies to and from a space station, it will have the ability to operate in orbit for a week and, therefore, can serve as a small space station-observatory until a bona fide space station is in operation. Engineers working on the shuttle believe that it can eventually replace all rocket launchers. In so doing the shuttle will cut the cost of building spacecraft by as much as a third according to some estimates. This will be possible because the spacecraft will no longer require elaborate protection against the crushing forces of rocket launches. Early NASA estimates were that the shuttle would pay for itself in five to six years, assuming 30 flights per year.

Despite these impressive characteristics of the shuttle and also the appeal of having a permanent space station in orbit, both of these programs for the next decade in space had their opponents. Rep. Joseph Karth (Dem., Minn.), chairman of the House Science and Astronautics Committee’s Space Science and Applications Subcommittee, believes that much more research is needed before a commitment is made to go ahead.

Even with this kind of opposition, the House of Representatives and Senate space committees authorized $160 million for shuttle-space station work in fiscal 1971.

Space Tug and Nuclear Shuttle

While priority was being given the earth-to-orbit shuttle and the space station, preliminary work was also under way on the space tug and the nuclear shuttle. Preliminary feasibility studies on the tug were due from contractors early in 1971. Early concepts foresaw the tug as a vehicle capable of operating in either the manned or unmanned mode. As a manned vehicle it would be able to carry a payload of 5,000 to 10,000 lb. from a lunar orbiting space station down to the moon’s surface. Unmanned, it might land as much as 70,000 lb. on the moon to aid in the buildup of a lunar outpost. It could support a manned expedition—three astronauts—as long as 28 days on the lunar surface.

NASA’s grand design calls for the tug to come into operation about two years after the nonnuclear earth-to-orbit shuttle. A nuclear-powered shuttle would then be ready soon after that. The latter would be able to boost a payload of about 175,000 lb. from earth orbit to a low orbit around the moon.

Permanent Space Station

NASA invested approximately $6 million in fiscal 1970 on space station studies. It had $30 million to continue the work in fiscal 1971.

Under the present concept, the first permanent station would be designed for a lifetime of ten years. It would be laid out with the care and long-range planning that goes into a major research facility on earth. The station would have a crew of three or four astronauts in charge of its operation, with the rest of its residents working full-time on research projects.

The first station, like Skylab, will be a trailblazer for bigger and better things to come if NASA’s present strategy is accepted. After the permanent space station, scientists hoped to establish a space base where dozens or even a hundred or more men would work at pursuits ranging from pure science to the manufacturing of materials that can be better managed without the burden of gravity.

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