Skylab's Fiery Fall

(6 of 7)

Originally, NASA had proposed in 1968 the $2.6 billion orbiting laboratory program. At that time extra rockets capable of keeping Skylab in space almost indefinitely were considered. The craft's ability to stay in orbit would be reinforced, if necessary, by astronauts transported up to it in a convenient space shuttle, then also on the NASA drawing boards. But under budgetary pressures both vehicles were simplified—and both developed unanticipated technical problems. So when Skylab's orbit began to slip, there was no shuttle to come to its rescue.

In fact, Skylab's history of glitches demonstrated both the futility of taking technological shortcuts and the agility of men working in space to remedy unexpected ailments. When Skylab was launched by a Saturn 5 booster rocket on May 14, 1973, a large section of its meteoroid and heat shield ripped away, taking one of its prematurely extended solar-energy wings with it. A second wing jammed in a retracted position. The craft both overheated in orbit and was dangerously underpowered. But in the space age's first salvage mission, on May 25, 1973, Astronauts Charles ("Pete") Conrad Jr. and Joseph Kerwin entered the overheated space lab and rigged a makeshift umbrella to shade the vehicle's bald spot, then spent a harrowing four hours outside the stricken craft freeing the stuck wing. During a second manned mission, on July 28,1973, the lab's thrusters sprang leaks—and a crash program to prepare a vehicle to rescue the three astronauts was undertaken. The astronauts shut off the leaking system, and the rescue mission proved unnecessary. On the third and final mission, on Nov. 16, 1973, Astronauts William Pogue and Edward Gibson struggled for three hours outside Skylab in getting a vital radar antenna adjusted and repaired.

In the course of its troubled flights, Skylab crews established an endurance record of 84 days in space—a mark since surpassed by Soviet cosmonauts. More than 50 scientific, technical and medical experiments were conducted. Some 183,000 unprecedented pictures of the sun were snapped through Skylab's telescope.

Ironically, despite NASA'S concentration on solar research with Skylab, the agency's failure to anticipate the extent of sunspot activity during the vehicle's years in orbit contributed substantially to the craft's death. Russian scientists as well as America's own National Oceanic and Atmospheric Administration had predicted considerable solar disturbances, including great magnetic storms and solar flares. When they erupted in 1977 and 1978, they warmed the gases in the earth's outer atmosphere, increasing the drag on Skylab. Never fully powered because of its lost solar wing and failing batteries, the craft began to slip ever closer to earth.