10 things to know about Skylab, America's first manned space outpost

NASA launched Skylab, America’s first space station, into space 50 years ago in May 1973, and it would make space history in ways its builders wanted and ways they would have gladly missed.

From the start of planning, engineers and scientists saw Skylab as the place to answer questions about long-term missions in space. Also anticipated - and achieved - were much better views of the Earth, the Solar System and the Sun once Skylab’s cameras moved outside the Earth’s atmosphere.

NASA’s Marshall Space Flight Center in Huntsville was a big part of the Skylab team from the beginning. Astronauts and engineers spent a total of 171 days practicing how to work in zero gravity in Marshall’s giant water tank. And after NASA headquarters approved the project, the center worked “closely with McDonnell Douglas, the prime contractor for the workshop unit, to convert a Saturn IB stage into a habitable module containing living quarters and support systems as well as experiment areas,” Marshall’s official history says. Marshall engineers also worked on the lab’s zero-gravity showers, toilets, sleeping bags, exercise gear and kitchen facilities.

Based on those NASA history accounts, here are 10 things to know about the mission, the spacecraft, the memorable moments and the challenges. It’s a list that could easily contain another 10 events and 10 more after that:

1. What was Skylab actually?

Skylab’s core was built from an empty rocket fuel tank that weighed 170,000 pounds, the heaviest spacecraft at that time. From the start, it was a design and technical challenge. Up and down don’t exist in space, a fact that everything inside must deal with. The life support system had to work over months not days or weeks as in earlier flights. The habitat needed a supply of energy it eventually found in solar arrays and it needed places to store everything humans might need for a long stay. Astronauts and engineers would spend a total of 171 days there over three missions.

2. How big was Skylab?

Skylab was also an assembly of modules. The command and service module built by Rockwell International got astronauts to space and back to Earth and was 34 feet long and 13 feet wide. The docking adapter built by Martin Marietta was 17 feet long and 10 feet in diameter. The solar observatory built by Marshall was 13 feet long and 11 feet in diameter. The airlock was almost 18 feet long and 22 feet wide at its greatest diameter. And the “workshop” built by MDAC-Western as the “primary living and working area” was 48 feet long and 22 feet wide.

3. When exactly did Skylab launch and what went wrong almost immediately?

The “Skylab space station,” as NASA calls it, launched from NASA’s Kennedy Space Center May 14, 1973. Sixty-three minutes after liftoff, its “meteoroid shield” designed also to shade the workshop in orbit, “deployed inadvertently” in NASA’s words and exposed the laboratory to the Sun’s rays.

4. What were the ‘10 days of trial’?

The meteor shield failure was the beginning of a “10-day period in which Skylab was beset with problems” that had to be fixed, NASA says. Engineers, managers and other astronauts worked around the clock at NASA Marshall and Johnson Space Center to lower the temperature and design and deploy arrays that eventually blocked the Sun and allowed the missions to proceed.

5. Who flew in Skylab?

Nine astronauts flew in Skylab and six more were backup crew. NASA’s history notes the commander and pilot of each crew were trained spacecraft and aircraft pilots with “strong engineering backgrounds.”

The nine astronauts who lived and worked in Skylab were Charles Conrad, Jr., Paul Weitz, Joseph Kerwin, Alan Bean, Jack Lousma, Owen Garriott, Gerald Carr, William Pogue and Edward Gibson.

Garriott, who lived in Huntsville, died at Huntsville Hospital in 2019 when he was 88. He was the science-pilot for Skylab 3, the second crewed Skylab mission, and was in orbit from July 28 to Sept. 25, 1973. His crewmates were Commander Alan Bean and Pilot Jack Lousma. The crew accomplished more than its mission goals while completing 858 revolutions of the Earth and traveling some 24.5 million miles.

6. What was the “day off”?

In February 1974 after six weeks of flight and performing many experiments, the Skylab 4 crew of astronauts William Pogue, Edward Gibson and Gerald Carr hit the exhaustion wall and announced an unscheduled day off. They turned off communications links, reports say, and spent the day resting and looking at the Earth from space. A compromise followed that gave astronauts designated rest periods and more control over when to do routine chores. Neither of the three flew in space again.

7. What did Skylab accomplish?

First and arguably most important, Skylab was proof to any skeptical experts that human beings could design and launch spacecraft that would allow them survive and work in space.

8. What were some important research findings?

Astronauts did solar research and studied the Comet Kohoutek with clarity impossible from Earth. The three crews looked at the Sun in detail not seen before and got the same detailed look at Earth and its resources. They conducted 270 experiments in everything from biomedical sciences to solar astronomy.

9. How did Skylab end?

In late 1978, NASA engineers discovered that Skylab’s orbit was “eroding” or coming closer to Earth. “Skylab had become a 77-ton loose cannon,” the website history.com said in its account. NASA had planned to use its new space shuttle to boost the lab into an orbit for another five years. But the shuttle was delayed and Skylab was coming down in July, 1979. NASA fired its boosters aiming for the Indian Ocean and its large pieces did land there. Other pieces fell in western Australia, but no one was injured.

10: Where can I learn more?

Facts, stories and images about Skylab are as close as your computer. Here’s a link to NASA’s official Skylab history. If you’re in or passing through Alabama, the U.S. Space & Rocket Center in Huntsville is the Marshall Space Flight Center’s official welcome center and custodian of a collection of America’s early space history. Its exhibits include a same-size training model of the Skylab laboratory, the largest piece of recovered Skylab debris, and docents who worked on the project and volunteer at the center to talk with visitors.

The rocket center has events celebrating the 50th anniversary this summer including:

Future events at the rocket center include:

• “The Science of Skylab,” Sunday, June 18, at 2 p.m. in Discover Theater – This discussion focuses on the range of experiments done during Skylab’s three missions and how NASA first engaged students across the country to contribute their ideas for scientific research.
• “Lessons on Living in Space: Skylab,” Sunday, July 2, 2 p.m. in Discover Theater – Skylab’s missions were a key step in learning the effects of microgravity on humans and equipment during long-duration stays in space. Lessons from Skylab helped drive the design and function of today’s International Space Station.
• “Saving Skylab” Documentary and Panel Discussion, Thursday, Aug. 17, at 6 p.m. - National Geographic Theater in the Davidson Center for Space Exploration. This documentary and discussion will show the heroic efforts to repair the solar arrays on the Skylab orbiter after they were badly damaged in liftoff. Without those repairs, Skylab would have been virtually powerless and useless.

(An early version of this story said Skylab was the world’s first space station. On April 19, 1971, the Soviet Union placed in orbit Salyut, which was the world’s first space station)