Skylab Proved Feasibility of Long-Duration Spaceflight

June 16, 2021

As the crew of Skylab 2 departs, the gold, parasol-like Sun shield covers the main portion of the space station. The solar array at the bottom was the one freed during a spacewalk. The four, windmill-like solar arrays are attached to the Apollo Telescope Mount used for solar astronomy.

America’s First Space Station – Part 2

By Bob Granath

Launched unpiloted on May 14, 1973, Skylab was a complex orbiting scientific laboratory that set the stage for the International Space Station of today and long-duration missions to the Moon and Mars in the future. Three crews of astronauts performed microgravity experiments for up to three months in a shirtsleeve environment. The program also provided information about how humans adapt to work during long periods of weightlessness.

Click here to learn more about the development of Skylab.

During the Saturn V liftoff, Skylab station was damaged when its micrometeoroid shield separated from the workshop and tore away, taking one of two main solar panel arrays with it and jamming the other. When the Skylab 2 crew of Pete Conrad, Joe Kerwin and Paul Weitz arrived, a spacewalk to free the stuck solar panel and other repairs were successful.

Skylab 2 commander Pete Conrad undergoes medical examination by science astronaut Joe Kerwin. Conrad simply rotated his body to an upside down position to facilitate the procedure. Learning the effects of microgravity on humans during long-term spaceflight was a principal goal of Skylab. Photo credit: NASA

With the Skylab 2 mission back on track, the crew focused on the primary goals of the program — studies in materials processing in microgravity, Earth observations, expanding knowledge of solar astronomy and proving that humans could live and work in space for extended periods.

The longest American spaceflight at that point was the 14-day mission of Gemini VII astronauts Frank Borman and Jim Lovell in 1965. Skylab 2 would double that record and show that the astronauts adapted well.

“Mobility around here is super,” Conrad said during the 28-day mission. “Every kid in the United States would have a blast up here.”

Following splashdown in the Pacific Ocean and recovery of Skylab 2 on June 22, 1973, NASA Administrator James Fletcher had high praise for the crew and the entire agency-industry team.

“For the first time, a crew of astronauts has returned from an extended tour in a space laboratory,” he said. “All of the objectives for this mission have been completed.”

Riding Along On a ‘Magic Carpet’

On July 27, 2013, a gala took place at the Kennedy Space Center’s Apollo/Saturn V Center celebrating the 40th anniversary of Skylab. The event featured Skylab astronauts, from the left, Paul Weitz, Alan Bean, Jack Lousma, Jerry Carr, William Pogue and Edward Gibson recalling experiences during their missions. Photo credit: NASA/Kim Shiflett

Skylab 3 launched the second crew on July 28, 1973, with Alan Bean, Owen Garriott and Jack Lousma aboard.

On July 27, 2013, the Astronaut Scholarship Foundation hosted a dinner at the Kennedy Space Center’s Apollo/Saturn V Center celebrating the 40th anniversary of Skylab. Six Skylab astronauts who flew the missions to America’s first space station participated in a panel discussion during the event. They spoke about living and conducting groundbreaking scientific experiments aboard the orbiting outpost.

Skylab 3 pilot Lousma noted that spacewalks were a crucial part of Skylab, paying dividends for the future.

Skylab 3 pilot Jack Lousma participates in a spacewalk on the Aug. 6, 1973. Lousma described the experience like "You're riding along on this 'magic carpet.’" — *Skylab 3 pilot Jack Lousma participates in a spacewalk on the Aug. 6, 1973. Lousma described the experience like “You’re riding along on this ‘magic carpet.’” Photo credit: NASA*

“We developed the procedures and techniques for doing effective spacewalks on Skylab that were used so successfully in putting together the International Space Station,” he said.

Lousma described spacewalking from the viewpoint of an astronaut.

“From outside you can see the entire Earth in a three-dimensional perspective,” he said. “You’re riding along on this ‘magic carpet.’ There’s no vibration, no sound, and a sunrise and sunset every hour and a half. You just want to stay out there.”

Skylab 3 science astronaut Owen Garriott operates the Apollo Telescope Mount from a console in the Skylab space station. Observations of the Sun were a primary achievement of the program. Photo credit: NASA

Early in the mission, Garriott and Lousma performed a spacewalk to erect a new twin-pole solar shield that provided better thermal control for the remainder of the Skylab missions.

The second crew returned to Earth Sept. 25, 1973, following 59 days in orbit.

Skylab 4 originally was planned for a mission of about the same length. When the final Skylab expedition was extended to 80 days or more, NASA’s Preflight Operations Branch at Kennedy, under Raul “Ernie” Reyes, was given the challenge to squeeze another 980 pounds of food, film and equipment into the Apollo command module. Using Reyes’ “a place for everything, and everything in its place” philosophy, his team succeeded in using every cubic inch of storage space.

‘We’ve only just begun to explore.’

On Nov. 16, 1973, astronauts Jerry Carr, Ed Gibson and Bill Pogue lifted off from Launch Complex 39B at NASAs’ Kennedy Space Center aboard their Apollo spacecraft atop a Saturn 1B rocket. Photo credit: NASA

On Nov. 16, 1973, astronauts Jerry Carr, Ed Gibson and Bill Pogue lifted off. During their 84-day mission, the Skylab 4 crew continued the comprehensive research programs. They held the United States’ spaceflight endurance record until Americans spent up to six months working aboard the Russian space station Mir in the mid-1990s and astronauts now have spent up to a year aboard the International Space Station.

During the 40th Anniversary Gala, Skylab 4 commander Carr spoke of the value of the longer mission.

“We learned a lot of lessons on Skylab 4,” he said. “It really turned out pretty well for us.”

Those lessons included how tasks requested by Mission Control and principal investigator scientists on the ground can be best-scheduled and coordinated with astronaut crews aboard Skylab. Changes in the approach allowed the astronauts time to finish tasks, transition and reflect on their work. The result was an incredibly productive mission and improved processes for future operations.

Gibson, who served as Skylab 4’s science pilot, spoke of the Apollo era leading to the first lunar landings and the Skylab space station.

“Apollo was really a great program that required us to develop new technologies,” he said. “That put us in a more competitive position. What we got back from it economically was at least two to three times what we put into it.”

Skylab 4 commander Jerry Carr flies the astronaut maneuvering equipment experiment in the forward compartment of the Skylab space station. The jet-propelled backpack was designed to demonstrate the unit's flying qualities. The effort helped pave the way for use of the Manned Maneuvering Unit that aided spacewalkers during the Space Shuttle Program. — Skylab 4 commander Jerry Carr flies the astronaut maneuvering equipment experiment in the forward compartment of the Skylab space station. The jet-propelled backpack was designed to demonstrate the unit’s flying qualities. The effort helped pave the way for use of the Manned Maneuvering Unit that aided spacewalkers during the Space Shuttle Program. Photo credit: NASA

Gibson also looked ahead to efforts that will, again, venture beyond low-Earth orbit.

“When you think about it, we’ve only just begun to explore,” he said. “There’s so much more to be done.”

Skylab 4 completed the Skylab Program when their Apollo command module splashed down in the Pacific Ocean on Feb. 8, 1974.

Following the recovery of Skylab 4, Fletcher stressed the importance of the program’s accomplishments for the future of human spaceflight.

“It has moved the space program from the realm of the spectacular, into a new phase that can be characterized possibly as almost businesslike,” he said. “It has contributed to an orderly transition from the Apollo era to the Space Shuttle.”

The empty Skylab’s orbit decayed with the station re-entering Earth’s atmosphere on July 11, 1979 scattering debris over the Southeastern Indian Ocean and across a sparsely populated section of Western Australia.

Skylab’s Achievements

Successful in all respects in spite of early mechanical difficulties, three crews occupied the Skylab workshop for a total of 171 days, 13 hours. It was the site of nearly 300 scientific and technical experiments: medical experiments on humans’ adaptability to zero gravity, solar observations and detailed Earth resources experiments.

Early in the Skylab 3 mission, Owen Garriott and Jack Lousma performed a spacewalk to erect a new twin-pole solar shield seen in this photograph taken by the Skylab 4 crew as they began the trip home on Feb. 8, 1974. Photo credit: NASA

Involving scientists from 28 nations, Skylab demanded the highest degree of cooperative effort from the world’s scientific community. The astronauts completed a revealing study of the Sun. Crews also manufactured alloys, grew perfect crystals and learned how to work in the microgravity environment of space.

Additionally, when the Skylab crews work was finished, the science teams were able to correlate the data refining their ability to more accurately observe and predict phenomena on Earth such as crop growth, weather and changes in the environment.

Carr summed up the program as he looked back over the years of planning and the three expeditions.

“Skylab started as a dream we had for seven and a half years,” he said. “We set a goal and achieved it.”

Lousma noted that the program helped pave the way for long-duration missions in low-Earth orbit and a return to the Moon along with flights to Mars lasting for more than a year.

“Flights of 28, 59 and 84 days were forerunners of what we are doing now aboard the International Space Station,” he said. “The fact that we could work in space for longer periods is one of the things we were able to prove during Skylab.”