Skylab (1973-1979): America's First Space Station

Skylab was the first space station of the United States, launched on 14 May 1973. Badly damaged on the way to orbit, it was saved by the first of three crews, who between them spent 171 days aboard and studied the Sun, Earth and the human body. Empty since 1974, it fell back to Earth on 11 July 1979, scattering debris across Western Australia.

Background

As the Apollo Moon landings wound down, NASA looked for ways to use its leftover hardware. The Apollo Applications Program proposed turning a Saturn rocket stage into an orbiting laboratory. The final design used an S-IVB third stage, fitted out on the ground as a two-storey workshop and launched on a Saturn V, the last of these rockets to fly.

Skylab weighed about 77 tonnes. It combined the orbital workshop, an airlock module, a docking adapter and the Apollo Telescope Mount, a solar observatory with its own windmill-like solar panels. Crews travelled up in Apollo command and service modules. The Soviet Union had launched the first station, Salyut 1, two years earlier.

A damaged launch

About 63 seconds after liftoff, the shield designed to protect the workshop from micrometeoroids and the Sun’s heat tore loose. It ripped away one of the two main solar wings and left the other jammed closed by debris.

In orbit, the station was short of power and its interior heated to well over 40 degrees Celsius. The first crew’s launch was postponed while engineers on the ground hurried to design a fix.

Three crews

The first crew, Pete Conrad, Joseph Kerwin and Paul Weitz, launched on 25 May 1973. They deployed a parasol-like sunshade through a small scientific airlock, cooling the station. On 7 June Conrad and Kerwin made a spacewalk to cut the debris holding the remaining solar wing, which then swung open and restored much of the power. They stayed 28 days.

The second crew, Alan Bean, Owen Garriott and Jack Lousma, flew from 28 July to 25 September 1973, a stay of 59 days. They erected a second sunshade over the first and carried out an extensive programme of solar observations and Earth photography.

The third crew, Gerald Carr, Edward Gibson and William Pogue, launched on 16 November 1973 and returned on 8 February 1974 after 84 days, a record that stood until a Soviet crew exceeded it on Salyut 6 in 1978. They observed Comet Kohoutek and recorded thousands of images of the Sun.

Science and life aboard

The Apollo Telescope Mount produced detailed observations of solar flares and of coronal holes, regions of the Sun’s outer atmosphere now known to release fast streams of solar wind. Cameras and sensors mapped Earth’s resources, and medical studies showed how the body adapts to weightlessness over months.

Skylab was roomy compared with earlier spacecraft. It had a shower, separate sleeping compartments and a wardroom with a window, features that informed the design of later stations, including the International Space Station.

Myths and facts

The third crew is sometimes said to have gone “on strike”. Accounts by historians and the crew describe something narrower: an overloaded schedule, frustration on both sides, and an unplanned day of rest in late December 1973, after which ground control and the crew agreed to a more flexible workload. The episode became an early lesson in managing long-duration missions.

Another story holds that Skylab’s debris caused damage or injuries in Australia. In fact the pieces fell in a thinly populated area, and the most notable effects were a souvenir hunt, a newspaper prize for the first fragment delivered and the light-hearted littering fine.

The fall of Skylab

NASA hoped the Space Shuttle could later boost Skylab to a higher orbit, but the Shuttle was delayed, and high solar activity heated and expanded Earth’s upper atmosphere, increasing drag. Re-entry became inevitable, and the approaching fall drew worldwide media attention.

On 11 July 1979 controllers changed the station’s orientation to try to bring it down over the ocean. It broke up over the Indian Ocean, but some debris landed in Western Australia, around Esperance and across the region to the east. No one was injured. The Shire of Esperance issued NASA a 400-dollar fine for littering, which went unpaid until an American radio host raised the money in 2009.

Timeline

• 1973, 14 May: Skylab is launched on the last Saturn V and is damaged during ascent.
• 1973, 25 May: The first crew launches and deploys a sunshade.
• 1973, 7 June: A spacewalk frees the jammed solar wing.
• 1973, 28 July: The second crew begins a 59-day stay.
• 1973, 16 November: The third crew launches for an 84-day mission.
• 1974, 8 February: The last crew returns to Earth.
• 1979, 11 July: Skylab re-enters over the Indian Ocean and Western Australia.

Why it matters

Skylab showed that astronauts could repair a crippled spacecraft in orbit and live productively in space for months. Its experience shaped the long-duration stations that followed.