The National Aeronautics and Space Administration, reeling from the loss of the space shuttle Challenger and its crew, now says that it wants to use unmanned rockets to loft some satellites into orbit. Better late than never.
It has been clear for more than a year that old-fashioned expendable rockets offer a cheaper, more reliable way of putting commercial and military satellites into orbit than the complicated and finicky shuttles do. Rockets such as Deltas and Atlas-Centaurs are relatively simple and have excellent success records. The only reason that satellite launches remained with the shuttles despite numerous malfunctions was the space agency's longstanding commitment to the shuttle as America's sole space workhorse. Without the satellite launches, there would not have been enough work for the shuttles to keep them flying.
That justification, which has been shaky for years, was dealt a final blow by the Challenger accident. In recent days a number of astronauts--led by John W. Young, the chief astronaut, and Sally Ride, a member of the commission investigating the disaster--have publicly complained about safety problems with the shuttles that were downplayed or swept aside altogether in NASA's relentless effort to maintain its launching schedule. The agency tentatively plans to resume shuttle launches next February, but it is likelythat the remaining shuttle fleet will be grounded for much longer than that.
When the shuttle project was approved by Congress in the early 1970s, it seemed like a good idea to phase out the expendable rockets of the space program. The shuttle was expected to be cheaper because it was reusable. But things didn't turn out that way. One penalty for NASA's taking so long to realize that is the months that it would take for expendable launchers to start rolling from assembly plants even if the order to build were given today.
Several years ago the Air Force decided that it needed to continue using expendable rockets for its military satellites because the shuttle's schedule was too unpredictable. Even before that the European Space Agency concluded that the abandonment of expendable launch vehicles by the United States opened a market niche for its own rocket, the Ariane. The Europeans began signing up commercial customers and now have a full launch schedule, including many American users.
The manned space program is a valuable and worthy endeavor that has important commercial and scientific goals. It is part of mankind's eternal quest to explore and to understand. The space shuttles should resume flying when their safety is assured. But they should be used only for tasks that require the presence of humans. Unmanned rockets can put most satellites into orbit, although some military satellites have been designed for the shuttle and are too big and too heavy for expendable rockets.
But NASA's plan to shift routine satellite launches to rockets, and the possibility that it eventually will encourage the development of a commercial rocket industry, is the right idea. It should obviate the need for building a $3-billion replacement for the Challenger. Better to put that money into improving the existing shuttles and developing the next generation of rockets.