Introduction - Skylab Mission
The Skylab space station blasted off from NASA Kennedy Space Center on 14 May, 1973, carried aboard a giant Saturn V launch vehicle. The empty craft returned to earth on 11 July, 1979. Debris from the craft landed in the Indian Ocean and on parts of remote sections of western Australia. As Skylab facts go, this last one may be the most well-known.
Skylab - a Historical Piece
Skylab was the US’s first space station, and only the second space station visited by a human crew (Salyut 1 was the first.). The 100-ton craft, the only one to be launched by NASA alone, was visited three times by space crews during 1973 and 1974. Crews were launched in Apollo-like command modules on Saturn IB launch vehicles on 15 May, 28 July, and 16 November, 1973.
Skylab Mission Objectives
As America’s first scientific experiment station in space, Skylab had two main goals. The first goal was to prove that humans could live and work in space over extended time periods and the second was to amass a set of Skylab facts to build the knowledge base of solar astronomy with space-based observations. Despite mechanical difficulties that began during the launch, the crews that later visited stayed on Skylab for a total of 171 days. Skylab facts collected included extensive medical data on humans’ adaptability to zero gravity conditions, observations of the sun, and experiments involving earth resources.
Overall, Skylab cost $2.6 billion, which would be on the order of $11 billion in 2010. This was somewhat of a bargain at about one ninth the International Space Station’s cost. The collection of Skylab facts proved to be quite cost effective, despite its early problems and unexpected demise.
Problems and Solutions
Skylab experienced its first problem a minute after liftoff in 1973, when the meteoroid shield that was made to shade the Skylab workshop deployed unexpectedly. It was actually torn from the station due to atmospheric drag. This and several other problems had to be corrected before Skylab became safe for manned missions.
One of these problems was that when the meteoroid shield ripped off, it jostled the mounting of the workshop’s solar array wing, causing it to partially deploy. Subsequently, the exhaust plumes from the second stage retro rockets blew the solar array off into space. Another consequence was that another solar array wing could not open enough to generate power.
But pretty much everything else went according to plan, and scientists on the ground at NASA Marshall Space Flight Center and elsewhere worked feverishly to position Skylab so that it could function optimally in its somewhat compromised state. The first crew was able to get the one solar array wing opened fully, restoring it to function and making the rest of Skylab’s mission possible.
After the crews left and some more engineering tests were run from the ground, Skylab was moved into a stable attitude and its systems were shut down. Scientists expected it to stay in orbit for another 8 to 10 years. But in the fall of 1977, it was discovered that the craft was no longer in a stable attitude due to greater than expected solar activity. Less than two years later, on 11 July, 1979, the debris from Skylab fell to earth, scattered in the southeastern part of the Indian Ocean and over parts of western Australia.