American Notes

It had been more than five years since an American walked in space, but the crew of the shuttle Atlantis did not seem rusty. On a first, unscheduled 4 1/ 2-hour jaunt, astronauts Jerry Ross and Jay Apt freed a balky antenna on an observatory satellite, permitting the $617 million device to be placed in orbit. The astronauts later tested sleds that haul large objects through space on a rail.

The success of last week's mission, however, did not settle the ongoing debate about the value of manned spaced flights. NASA officials have long insisted that human crews are vital because even the most sophisticated robots lack the ability to respond to unexpected situations. If the U.S. is serious about exploring the solar system, they say, unmanned probes to distant celestial bodies must be followed by missions involving humans.

Critics counter that unmanned, expendable rockets can loft most satellites into orbit at far less cost and with much less risk than the reusable shuttle, which has been plagued by technological glitches. The argument will heat up this spring as Congress decides whether to fund a $30 billion orbiting space station. NASA plans to use the shuttle to ferry up astronauts to assemble the station, then supply it with unmanned rockets. If the lawmakers decide to scrub the station, the shuttle will be without a clearly defined role.