Challenger - sky-high repair

The Challenger astronauts' service call in space has been a triumph of success-oriented thinking. Even when the Solar Max satellite temporarily eluded capture, the shuttle team gave little heed to the possibility of failure. Neither did the US public, which sent a flood of phone calls and letters saying, in effect, ''We knew you could do it.''

Now, with Challenger back on the ground and a rejuvenated Solar Max observatory orbiting 308 miles overhead, a new era of space operations seems definitely to have begun. Throwaway satellites are no longer practical, except, perhaps, for some special purposes such as communications. These latter satellites are in an orbit 22,300 miles high and beyond the reach of the shuttle. But one day they, too, will likely be serviced by vehicles that will bring them down to the level of the shuttle or a space station.

Meanwhile, most scientific satellites have become too costly and complex for a throwaway economy. Solar Max cost some $100 million in 1979 dollars. About $77 million was US-funded. The balance is the value of instruments contributed by European countries. The next generation of satellites - such as the space telescope or a gamma ray observatory - will cost several times as much. To abandon one of these, or use less than its full capacity, just because a few parts fail would be as foolish as giving up on a automobile because a tire wears out or the fuel pump quits.

Whether the service-call strategy can be applied to satellites which, unlike Solar Max, were not designed for it, is unclear. But studies are under way to see if repairs can be made to the Western Union and Indonesian communications satellites which failed to reach proper orbit during the previous shuttle mission.