While the United States basked in the glow of the recent successful Challenger mission, the Soviet Union was savoring an extraordinary manned-spaceflight achievement of its own. Cosmonauts Vladimir Dzhanibekov and Viktor Savinykh had revived the dead Salyut 7 orbital station. This feat has been little noted by the Western press. Yet it is a timely reminder that the Soviet Union has become a formidable spacefaring power.
It is closing in on its goal of establishing a permanently manned orbital complex.
It has a program of planetary exploration that, in some ways, is leading the world.
It has a stable of advanced weather, communications, military, and scientific satellites.
It has even entered the commercial satellite-launching competition by offering to orbit Inmar communications satellites at about half the price quoted for the US shuttle or Western Europe's Ariane service. Inmar satellites serve merchant shipping.
Revival of the three-year-old Salyut 7 station illustrates Soviet spaceflight skill. Former Cosmonaut Konstantin Feoktiskov has aptly described it as a task in which the crew ``showed real bravery in very difficult circumstances.''
Soviet controllers lost contact with the craft when its power supply failed last winter. Cosmonauts Dzhanibekov and Savinykh could not use the Salyut radar and other automatic docking aids. They made a risky manual rendezvous and linkup with the 47-ton station, which took some 50 hours to complete.
As Mr. Feoktiskov, now a senior Soviet space official, has reported in Pravda, the cosmonauts found a total failure of the eight solar-powered Salyut batteries. Even the water supply was frozen. The repair team, launched June 5, had Salyut 7 back in operation by June 16. Unmanned Progress tankers have brought up new supplies. The cosmonauts replaced two Salyut solar panels in a five-hour ``spacewalk'' Aug. 2, demonstrating new semirigid spacesuits.
The cosmonauts have also helped service a new type of unmanned spacecraft which docked with their Salyut July 21. This appears to be a type of free-flying platform, a type of craft that would also accompany the planned US space station. Free fliers would co-orbit with the station while carrying out such tasks as manufacturing or scientific observing, either automatically or by remote control. Space-station crews could bring the platforms to their station for servicing.
There is considerable speculation and some photographic indication that the Soviets are testing a space shuttle of their own. However, Soviet spokesmen maintain they are only interested in investigating the basic technology. They repeatedly say, as Cosmonaut Alexander Serebrov told the magazine New Scientist last spring, that ``a space-aircraft is an extremely expensive means of transport.''
They say they prefer to use expendable rockets to launch the simpler spacecraft needed to build the permanent space station, which is their present main manned-spaceflight goal.
Beyond this, the Soviets are talking freely of an ambitious unmanned solar system exploration program. Their two Vega craft have recently dropped landers and balloon-carried probes into the Venus atmosphere. Now the Vegas are heading for a rendezvous with Halley's comet next March.
The Soviets plan to send a Lunar Polar Orbiter to make a complete mineralogical map of the moon -- including its uncharted polar regions -- in 1989 or 1990. This is a mission which NASA has sought for many years but has yet to have funded.
One of the Soviets' most intriguing projects is the Mars/Phobos mission to be launched in 1988. After surveying Mars, the two spacecraft involved are to make a close inspection of the Martian moons Phobos and Deimos.
Some Western observers view the Soviet progress with a renewed sense of East-West space competition.
While the situation undoubtedly has its competitive aspects, it might be more profitable to see in it a new opportunity for cooperation. Indeed, the Soviets appear to be seeking such cooperation for their solar system exploration.
They have invited -- and received -- the participation of some Western nations as well as Eastern-bloc countries.
The two Vega craft, for example, have US instruments on board, and NASA is helping to track them.
Perhaps, if US-Soviet relations improve with the forthcoming fall summit meeting, new cooperative projects in manned spaceflight might develop as well.
A Tuesday column. Robert C. Cowen is the Monitor's natural science editor.