ON a cloudless evening, you can see twinkling stars and gleaming planets. You may also see a glint from junk orbiting in the great ``landfill'' in the sky. Space debris, about which there have been several warnings in recent years, is a hazard we can no longer ignore. A new study by the congressional Office of Technology Assessment (OTA) concludes that ``unless nations reduce the amount of orbital debris they produce each year, future space operations could suffer loss of capability, loss of income, and even loss of life.'' The growing threat of shrapnel raises serious questions about the long-term safety of, among other ventures, both the Soviet MIR and the planned United States Freedom space stations.
Some experts within the American National Aeronautics and Space Administration (NASA) and the European Space Agency put things even more bluntly. They warn that, if the junk continues to accumulate at its present rate, the risk of collision will be too great for people to venture into orbit at all. Humanity's exuberant entry into space could end up imprisoning us on our planet for centuries.
That would be a silly outcome because it is both foreseeable and preventable. But it will take more decisive action than space-faring nations so far have mustered to avoid that fate.
Europe, the Soviet Union, and the United States have tried to minimize the likelihood of rockets and satellites exploding and creating even more debris. Over the next two years, the United Nations is likely to formalize guidelines for the safe use of space nuclear-power sources. These guidelines would have the force of international law.
However, the OTA points out that existing treaties and agreements are inadequate to halt the creation of space junk. Basic legal issues also are unresolved. Launching countries, for example, aren't liable for their junk. Therefore, OTA notes, they ``have no legal incentive to avoid generating orbital debris.''
The problem is further complicated by ignorance of what is orbiting Earth. More than 3,200 launches have released over 3,800 payloads since the space age opened in 1957. By rough estimate, these have left some 3.5 million pieces of drifting junk ranging in size from under a millimeter to complete satellites. Only a tiny fraction of this debris has been tracked and cataloged.
It clearly is time to stop picking at the edges of the space-junk problem. The United States has already shown some leadership in this field in trying to minimize on-orbit explosions and in tracking debris. Now it could take the lead in organizing a comprehensive effort within the United Nations to understand the problem fully and to lay down the legal basis for regulating space activity so as to curb orbital pollution.
The celestial ``landfill'' is filling up. Keeping this issue on the back burner will only buy needless trouble one or two decades hence.