There's a sense of deja vu around the US National Aeronautics and Space Administration (NASA) headquarters these days. President Reagan's new National Space Strategy recognizes the reusable shuttle as the gateway to space. It identifies a permanently manned orbital station, which takes advantage of that transport system, as the next logical step in opening up the space frontier. And it urges serious planning for the long-term logical steps of a base on the moon or a manned expedition to Mars.
NASA personnel with long memories recognize these as precisely the priorities defined by a major review of US space policy more than a decade ago.
At that time, President Nixon - constrained by a struggling economy and facing a public disenchanted with space extravaganzas - told NASA to curb its ambitions. The agency chose to develop the space shuttle and put off space stations and moon-base planning for sometime in the future.
Now that future has arrived. President Reagan - fired with enthusiasm for the ''high frontier'' and sensing that the time is ripe - has made an orbiting station the centerpiece of US civil space strategy.
Recalling this history during a recent White House press briefing, NASA Associate Administrator Philip E. Culbertson, director of the space station office, observed that the Soviets also had to make choices in the early 1970s. They took a different tack - opting to develop an orbiting station and making do with essentially the manned spacecraft technology of the 1960s. Now the two programs are again converging, with the US moving toward a station and the Soviets developing a reusable shuttle.
This combination of a permanently manned infrastructure on orbit and an airline-like transportation system is so obviously the way to go that other space-faring nations are warming to the concept, Mr. Culbertson noted. (See accompanying box for details of Western Europe's plans.)
Actually, he points out, it is misleading to speak of a space ''station.'' What planners have in mind is a multipurpose facility that, like a major research center on the ground, fulfills many purposes. It will have both manned and unmanned elements - platforms that fly co-orbitally with the manned complex and can be serviced by it or which, being in different orbits, will still be reachable from time to time from the station.
Such a facility is expected to provide an unprecedented ''freedom of space and power with a pressurized volume and crew to carry out ... Earth orbital observations and science.'' Culbertson said the complex should have more electric power available than ''the sum of all the electrical systems that we've placed in space so far.''
It will provide an environment for extended development and operation of processes that depend on weightlessness, such as production of new alloys or special pharmaceuticals. And it will act as an orbiting repair facility for equipment within the complex and for unmanned platforms flying with it, such as the Hubble space telescope. Due to be launched in 1986, the telescope is designed to be serviced from the shuttle and, eventually, from an orbital station.
What NASA has had in mind until recently has been a complex with several linked modules that would accommodate six to eight people and be served by the shuttle. It would be designed for a 20-year life (with maintenance and modifications) in an orbit 250 miles high and inclined 28.5 degrees to the equator. It would be accompanied by two large unmanned platforms - one orbiting with it and one in polar orbit. This system would cost an estimated $8 billion to design, build, and put into operation in the early 1990s.
NASA is relying heavily, however, on the advice of scientists who would be among the facility's main users. The major channel for such advice is the Task Force on Scientific Uses of Space Station, chaired by Prof. Peter Banks of Stanford University's electrical engineering department.
A principal conclusion of a task force meeting last month was that scientists would very much prefer a squadron of smaller platforms co-orbiting with the station than the two big ones NASA had envisioned. The meeting also urged a complex that could accommodate 10 crew members and would include a ''garage'' in which satellites could be serviced within a ''shirtsleeve'' environment rather than by space-suited astronauts.
Burton Edelson, NASA associate administrator for space science and applications, has said this task force's advice will be an important factor in space-station planning. He has assured the group that ''the scientists will be listened to. We will try to do what the scientists want to the best of our ability, and if we can afford it.'' Thus, he observed after the meeting, ''it is becoming clear it's not going to be a large co-orbiting platform and a large polar platform.''
At this writing, NASA was about to issue invitations for industry to bid on a series of studies needed to define the station in detail - studies to begin next spring. Dr. Edelson said that, while NASA can't completely redo the design concept guidelines it is asking these studies to address, it will make sure that the task force recommendations are considered.
It is unclear what such a change in concept would do to NASA's $8 billion cost estimate. In any event, that figure does not include the full expense of the space-station enterprise: It neglects launch, maintenance, and operating costs. The latter would include about $1 billion a year for six trips to ferry station crews back and forth on a two- to three-month rotation.
Professor Banks said total costs could run as high as $18 billion. Some scientists at the meeting put the figure at $25 billion, although NASA sees no basis for anything that large. Meaningful costs for the project will likely be hard to pin down until a detailed design is in hand.
Not everyone is enchanted with NASA's space-station planning. The congressional Office of Technology Assessment (OTA), in particular, charges in a recent report that the program is moving ahead without adequate knowledge of what actually will be needed in the future. While acknowledging that some sort of manned space infrastructure will be worthwhile, the OTA says NASA should proceed at a more modest pace, at less cost, and in response to specifically defined needs.
Answering such criticism, NASA's Culbertson explains: ''The space station is not a program. It's not a mission to Mars. It's not a landing on the moon. It's the development of a capability. We are always hard pressed to determine what sort of capability should be built into it. ... It would, really, be much better if we could wait until 1992 and see what we wanted in 1992 and then have it. We haven't figured out how to do that.''
Noting that ''the space station has been about the most studied subject NASA has ever undertaken,'' he asks rhetorically, ''Would it be different if we waited five years? It is hard for me to suggest the areas in which it might be different. I am sure that it would be different. It would also be five years later. So one can always say, 'Should one wait a little longer?' We think we've waited long enough.''