Skylab - The Story of the Space Station

Skylab was the first United States space station, launched by NASA, occupied for about 24 weeks between May 1973 and February 1974. It was operated by three separate three-man crews: SL-2, SL-3 and SL-4. Major operations included an orbital workshop, a solar observatory, Earth observation, and hundreds of experiments. On August 8, 1969, the McDonnell Douglas Corporation received a contract for the conversion of two existing S-IVB stages to the Orbital Workshop configuration. One of the S-IV test stages was shipped to McDonnell Douglas for the construction of a mock-up in January 1970. The Orbital Workshop was renamed "Skylab" in February 1970 as a result of a NASA contest. The actual stage that flew was the upper stage of the AS-212 rocket (the S-IVB stage, S-IVB 212). The mission computer used aboard Skylab was the IBM System/4Pi TC-1, a relative of the AP-101 Space Shuttle computers. The Saturn V with serial number SA-513, originally produced for the Apollo program—before the cancellation of Apollo 18, 19, and 20—was repurposed and redesigned to launch Skylab. The Saturn V's third stage was removed and replaced with Skylab, but with the controlling Instrument Unit remaining in its standard position. Skylab was launched on May 14, 1973 by the modified Saturn V. The launch is sometimes referred to as Skylab 1, or SL-1. Severe damage was sustained during launch and deployment, including the loss of the station's micrometeoroid shield/sun shade and one of its main solar panels. Debris from the lost micrometeoroid shield further complicated matters by becoming tangled in the remaining solar panel, preventing its full deployment and thus leaving the station with a huge power deficit. Three crewed missions, designated SL-2, SL-3 and SL-4, were made to Skylab in the Apollo command and service modules. The first crewed mission, SL-2, launched on May 25, 1973 atop a Saturn IB and involved extensive repairs to the station. The crew deployed a parasol-like sunshade through a small instrument port from the inside of the station, bringing station temperatures down to acceptable levels and preventing overheating that would have melted the plastic insulation inside the station and released poisonous gases. The crew conducted further repairs via two spacewalks. The crew stayed in orbit with Skylab for 28 days. Two additional missions followed, with the launch dates of July 28, 1973 (SL-3) and November 16, 1973 (SL-4), and mission durations of 59 and 84 days, respectively. The last Skylab crew returned to Earth on February 8, 1974. The crews consisted of: Skylab 2 - Pete Conrad, Joseph Kerwin and Paul Weitz Skylab 3 - Alan Bean, Owen Garriott and Jack Lousma Skylab4 - Gerald Carr, Edward Gibson and William Pogue Skylab's demise in 1979 was an international media event, with T-shirts and hats with bullseyes and "Skylab Repellent" with a money-back guarantee, wagering on the time and place of re-entry, and nightly news reports. The San Francisco Examiner offered a $10,000 prize for the first piece of Skylab delivered to its offices; the competing San Francisco Chronicle offered $200,000 if a subscriber suffered personal or property damage. A Nebraska neighborhood painted a target so that the station would have "something to aim for", a resident said.A report commissioned by NASA calculated that the odds were 1 in 152 of debris hitting any human, and odds of 1 in 7 of debris hitting a city of 100,000 people or more. Special teams were readied to head to any country hit by debris. The event caused so much panic in the Philippines that President Ferdinand Marcos appeared on national television to reassure the public. A week before re-entry, NASA forecast that it would occur between July 10 and 14, with the 12th the most likely date, and the Royal Aircraft Establishment predicted the 14th. In the hours before the event, ground controllers adjusted Skylab's orientation to minimize the risk of re-entry on a populated area. They aimed the station at a spot 810 miles (1,300 km) south-southeast of Cape Town, South Africa, and re-entry began at approximately 16:37 UTC, July 11, 1979. The Air Force provided data from a secret tracking system. The station did not burn up as fast as NASA expected. Debris landed about 300 miles (480 km) east of Perth, Western Australia due to a four-percent calculation error, and was found between Esperance, Western Australia and Rawlinna, from 31° to 34°S and 122° to 126°E, about 130–150 km (81–93 miles) radius around Balladonia, Western Australia. Residents and an airline pilot saw dozens of colorful flares as large pieces broke up in the atmosphere; the debris landed in the most unpopulated land on Earth, but the sightings still caused NASA to fear human injury or property damage. The Shire of Esperance light-heartedly fined NASA A$400 for littering, and Scott Barley of Highway Radio raised the funds from his morning show listeners in April 2009 and paid the fine on behalf of NASA

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