Closer to liftoff

THE US space program took a step this week toward recovery from the Challenger disaster. Workers at the Kennedy Space Center are getting ready to mate the shuttle Discovery to its solid-fuel boosters and outboard fuel tank. The launch is set for Sept. 3.

We share the workers' enthusiasm over the event. Tests of changes to the orbiter and to the boosters responsible for the Challenger explosion have been largely successful. Just as crucial are changes to NASA itself, including the way launch decisions are made. That process won't be truly tested until the agency has several launches behind it and a launch date arrives with marginal weather and technical snafus.

Improving shuttle safety is vital. So is the recognition that manned spaceflight is unlikely to be ``routine'' anytime soon. The risks associated with spaceflight can be intelligently managed; they should not, however, paralyze the civilian space program. A diverse fleet of manned and unmanned vehicles, now a US goal, is one way to address this paralyzation problem.

The Soviets stand ready to test their own shuttle; the Western Europeans recently launched the newest version of their Ariane rocket. It is more important than ever for the United States to maintain an active, well-rounded space program.