As the US space program moves through the 1980s, it will increasingly become a military venture.
This pleases some in Congress who are urging the Pentagon to do even more with space lasers and other ''Star Wars'' weaponry. But some, including former astronaut Harrison Schmitt (now a Republican senator from New Mexico), are concerned that this may come at the expense of other scientific space efforts.
Senator Schmitt and like-minded legislators may not be able to reverse the inevitable militarization of space, particularly with the success of the space shuttle. But they did win a significant victory recently when a Senate authorizing committee voted to make the Pentagon pay its own way for future military launches and payloads carried into space. In the coming year, that will amount to $409 million, a sum that originally was included in the National Aeronautics and Space Administration (NASA) budget but now must be borne by the Defense Department.
From the launching of the first Soviet sputnik to the reusable Space Transportation System, as the American shuttle is called, much of both countries' efforts in space has been directed at military advancement. But in recent years, this has accelerated just as detente has given way to greater superpower confrontation.
The Soviet Union, according to Pentagon officials, is several years ahead of the United States in developing a space-based laser weapon that could threaten American satellites and ballistic missiles. The US also is pushing ahead with such weaponry, but not as fast as some would like.
In a classified report last month, the General Accounting Office said directed-energy technology (involving laser, particle, and microwave beams) ''may revolutionize military strategy, tactics, and doctrine.'' It urged the Pentagon to accelerate its development of laser weapons.
Many top Air Force officials are playing down space weaponry, however. Meeting with Pentagon reporters over breakfast recently, the Air Force's research director, Lt. Gen. Kelly Burke, cited the great technological problems presented by building, transporting, and accurately using space lasers. He noted the antisatellite missile that the Air Force soon will test fire from high-flying jet fighters as a better system for the near future.
Overall, however, the military aspects of the US space effort are gaining as nonmilitary research projects account for less and less of NASA's spending.
''Whereas NASA's scientific programs were a full 36 percent of the research and development budgets in 1979 and 1980, they constitute only 28 percent of the proposed 1983 budget,'' Senator Schmitt complained recently. ''Since 1980 the aeronautics budget of NASA has decreased by over 40 percent in constant dollars.
''The proposed fiscal year 1983 budget contains many programs only because they are of direct interest to the Department of Defense, while eliminating 12 major systems technology programs which would support a private aeronautics industry hard hit by foreign competition.''
Since 1979, Schmitt points out, NASA has canceled its obligation to supply a spacecraft for the International Solar Polar Mission, plans for a Venus mapping mission (although a modest mission now is being studied), and a rendezvous with Halley's Comet in 1986.
In criticizing the growing military use of the space shuttle, Schmitt says, ''The DOD should not have to be subsidized at the expense of our country's civil aeronautics and space programs.''
However, DOD support has been crucial to shuttle development all along and shuttle planning has always included the military applications.
According to a recent GAO report, the Pentagon will be the prime passenger aboard nearly half the shuttle flights through 1984, 114 out of 234.
''This is bad news for those who are concerned over cutbacks in NASA's space science activities,'' says Sen. William Proxmire (D) of Wisconsin. ''It means that more and more of each NASA budget will be spent on defense-related activities and less and less will be spent on civilian science.''
It was because of this that the Senate voted earlier this month to stop ''the free ride for the Pentagon,'' as Senator Schmitt puts it.
This is not likely to slow down the Defense Department's increasing role in space activities, however. In addition to antisatellite programs, defense planners are working on space-based communications and navigation systems, nuclear detection devices, and enemy missile warning capabilities.
The fourth flight of the space shuttle, scheduled for June 27, will include a military payload.