Return of the Humans ...

The 1960s were the first decade of Man in Space. The 1980s will be just as significant, but in a different way.

The launch and operation of the Space Shuttle have begun a new kind of space travel. Large numbers of men and women, astronauts and scientists, will soon travel almost routinely into space, not to explore an unknown and possibly dangerous environment, but to observe, work, and live in space.

The Space Shuttle flights, lasting from one to four weeks, will provide time for long scientific and biomedical experiments that have not been possible since the Skylab flights of 1973 1974. In the natural or "shirtsleeve" environment inside the Shuttle, instruments can be operated, modified, and even repaired by scientists on the spot. Among other missions, the Shuttle will carry a complete scientific laboratory called Spacelab into space. Chemical and materials-processing experiments will be done to investigate suitable applications of the weightless ("zero G") environment.

A major advantage of the Space Shuttle is that it makes possible more detailed biomedical experiments on the human ability to adapt and func tion in space. These studies are especially important for the future, because they will provide the information we need to plan longer missions for humans in space.

an illustration of an orbiting labratory stored in the Shuttle's cargo bay prior to deployment

A laboratory in space.
Spacelab, an orbiting laboratory facility provided by the European Space Agency and flown on NASA's Space Shuttle, will be instrumented with experiments designed by scientists from many different fields of space research. A few researchers, called payload specialists, may fly along with the astronaut crew, to conduct the experiments. Shown here is an artist's conception of Spacelab 2, which will conduct investigations planned by eleven U.S. scientific teams and by two groups in the United Kingdom. Fields of study include life sciences, astronomy, solar physics, plasma research, and liquid helium technology.

Looking beyond the Space Shuttle, there is much to be done before astronauts can set out for Mars, before we can staff permanent space stations or build bases on the Moon.

We must first discover whether people truly can live in space for long periods of time. What are the psychological effects of weightlessness? Can calcium loss from bones in space be controlled or reversed? What are the long-term effects of space radiations on human beings? Can humans read just to Earth's gravity after long periods spent in space? Some of the answers can be found in studies on Earth. For most of them, however, we need the experience that flights of the Space Shuttle will provide.

If humans are to live in space on a permanent basis, we must then design the systems that they will need. Our spacecraft systems to date - Gemini, Apollo, even the Space Shuttle -have all carried the full complement of supplies needed for their short missions, enough to allow for the consumption of food and the gradual exhaustion of oxygen. These systems are both wasteful and inadequate for long missions. For longer trips, we need to design life-support systems that will recycle water and oxygen over long periods of time. We also need to develop ways of producing food in space, whether from plants, from small animal farms, or even from the products of our own metabolism. We do not need these systems to operate the Space Shuttle, but we will need the experience from Space Shuttle to develop the systems for future use.

Because we have been so successful in going into space, serious consideration is now given to ideas that, not long ago, were found only in science fiction. Current scientific work shops and political debates focus on such possibilities as mining the Moon, building space-based solar power stations, even establishing sizable populations in space. We do not know yet if these things are possible. In the next few years, research, both on the ground and in space, should provide the answer to whether humans can be permanent residents of space and should illuminate the prospects for what can be accomplished there.