The Demise of Skylab July 11, 2012Posted by Lofty Ambitions in Science, Space Exploration.
Tags: Space Shuttle
Several weeks ago, we wrote a post called “Happy Birthday, Skylab” to commemorate the anniversary of the orbiting laboratory’s launch in 1973. Today marks the anniversary of Skylab’s demise in 1979, also on a Wednesday. The six-year run paved the way for the International Space Station we currently have orbiting above our heads.
The last Skylab mission, SL-4, lasted 84 days, ending on February 8, 1974. The three astronauts—Gerald Carr, William Pogue, and Edward Gibson—had never flown to space before and never would again. The shower was more trouble than Skylab crews thought it was worth, but the food was okay. This crew performed four spacewalks, did chores and science experiments, and took lots of photographs of Earth, a comet, and a solar flare. When they left, they closed but did not lock the hatch, hoping that another crew would someday visit.
That summer on 1979, Anna was thirteen years old, and Doug was twelve, and Skylab was on the evening news. We hoped Skylab’s demise would come on our side of the globe, so that we could watch its fiery decent. NASA, though, was working to make sure that the pieces to fell into the Pacific Ocean, so as to avoid hitting land and especially people. After all, the space object was the equivalent of a 77-ton, nine-story, little building. Far from the ocean, we didn’t see the show in person. NASA miscalculated the fall slightly, and Skylab didn’t burn up as fast as engineers expected, so there were some good-sized pieces that came through the atmosphere, and a few of them landed in Australia.
Time, in an article that hit news stands several days after Skylab fell, noted that people really shouldn’t worry about being hit by debris: “[O]n each of Skylab’s 90-minute orbits of the earth, nearly 67 minutes, or 75%, is spent over water. What all that means, contend NASA’s statisticians, is that the chance of any remnant striking a human being is only 1 in 152; the probability of any specific person being struck is 1 in 600 billion—far less than the chance of being hit by a bolt of lightning or winning a lottery.” On the other hand, according to the same article, the chance of debris—maybe that two-ton film vault—hitting inside a city with a population of more than 100,000 was estimated at one in seven. For comparison, a woman’s lifetime risk of breast cancer is estimated at one in eight, a lower risk.
Americans weren’t worried, though. An insurance representative, according to the Time article, assured folks that regular home owner’s policies covered any damage that might be caused by Skylab. At the time, we saw t-shirts and heard about parties to watch the event on television. Two San Francisco newspapers offered rewards to readers who could produce Skylab debris or evidence of being hit by debris. In an unusual move, NASA said that people who found debris could keep it. So when an Australian man did end up with a piece, he was flown to San Francisco to collect his money. A piece of Skylab, weighing more than a ton, was displayed during the Miss Universe pageant held in Australia on July 20. Skylab became part of the pop culture of our childhoods.
Had the space shuttle been ready to launch before 1979, it could have been used to push Skylab into higher orbit to extend the life of the science laboratory and keep it from falling back to Earth. Skylab had not been used after February 1974, after one unmanned and three manned missions, but it was still up there and operational enough to welcome another crew, so why not reactivate it? Once in higher orbit, the shuttle could have run missions to make necessary repairs and update the science equipment onboard. Folks even talked of expanding its size by adding modules. But the shuttle’s first launch didn’t occur until April 1981. Skylab had already met its end.