This year marks the 40th anniversary of Skylab, and as the first crew changeover date of July 28th came to pass, it seemed fitting to look back and celebrate the success and legacy of the nation’s original space station. Remembered for taking research to new heights and paving the way for future exploration into the solar system, Skylab hosted experiments with results that proved humans could adapt to microgravity and function effectively in that environment for months at a time.
Skylab, launched in 1973 atop a Saturn V rocket, served as a precursor to what we do in space today. “When we started the Skylab Program we had to make a lot of guesses about the best way to operate in space,” said International Space Station Program Scientist Julie Robinson, Ph.D. “Everything from how to plan the day, to how to have the crew exercise, to how to operate instruments on a human-occupied spacecraft. We owe so much to the pioneering crews, the operations teams on the ground and the scientists that paved the way. Skylab helped us define the problems for long-duration spaceflight, and now the International Space Station is solving them one by one.”
The Skylab Program led to new microgravity-based scientific and technological research and was an important stepping stone for the construction, operation and use of the current space station design. Special toilets, sleeping bags, exercise equipment and kitchen facilities were all designed to function in microgravity based on what we learned from Skylab.
The nation’s first space station served as the greatest solar and Earth observatory of its time, a microgravity lab, a medical lab and a home in the sky. Three Skylab crews completed more than 300 investigations to answer questions about our planet, the universe and living in space. The variety of research disciplines included human physiology, materials science, technology demonstration and even student experiments.
As a result of Skylab’s contributions, we now have a technological marvel circling the Earth at more than 17,000 miles per hour and roughly the size of a football field. The current International Space Station is a world-class laboratory that has been enabling scientific research in orbit for close to 13 years.
One of the greatest scientific legacies of Skylab is the collection of astronomical observations returned from the Apollo Telescope Mount. This instrument rack kept Skylab’s array of eight solar telescopes pointed at the sun during a period of extraordinarily high activity. Skylab's first commander, Charles "Pete" Conrad, said his command of Skylab meant more to him than his walk on the moon. He explained in a documentary that part of his reason for this viewpoint was being able to run the solar telescope and bring back an incredible amount of information that nobody had seen before. Today, spectrophotometers mounted on the outside of the International Space Station measure solar irradiance, the energy from the sun that reaches Earth. Solar irradiance information is significant to both Earth-based and space-borne communications systems as well as to our climate.
In addition to filming the sun, Skylab returned more than 40,000 photographs of the Earth giving valuable data pertaining to geographical, forestry and oceanic industries, to name a few disciplines benefiting from the astronauts' orbital perspective. Building upon those images captured by Skylab's crews, there now are more than 1 million photographs taken from the International Space Station of our home planet with standard cameras and thousands more with specialized cameras such as the Hyperspectral Imager, with specific studies including mapping the characteristics of tropical rain forests; agricultural crops, forests, and rangeland areas; urban/developed areas; water resources; geologic features; maritime/littoral zones, wetlands and coral reefs; etc.
Scientists now use more advanced technology, a growing foundation of knowledge and more time devoted to in-orbit studies to expand upon the important work started on Skylab. One key area of research traversing from Skylab to today’s space station is the concern for body mass and bone density loss, due to the microgravity environment. Scientists now know from these studies that sufficient resistive exercise and proper nutrition can maintain bone density during long duration spaceflights.
“Skylab took the first step of Americans living in space and doing useful science above the atmosphere at lengths not possible on the ground and for long duration periods,” said Owen Garriot, science pilot on Skylab 3. As medical technologies have advanced on Earth, so has our ability to understand the changes that occur in astronauts during extended periods of time in space.
Other medical breakthroughs like ultrasound training methods developed for use on the space station have been used by the American College of Surgeons to teach imaging techniques to technicians, doctors and hospitals. These techniques have applications for diagnosing injuries and illnesses in remote locations on Earth, disaster areas and war zones. Crew members have conducted Advanced Diagnostic Ultrasound in Microgravity exams on one another to determine the accuracy of ultrasound use to diagnose certain types of in-orbit injuries and illnesses, as well as to assess the feasibility of ultrasound for monitoring in-flight bone alterations.
Experiments aboard Skylab proved materials processing concepts while continued and advanced investigations taking place aboard on the International Space Station, like the colloid studies, have led to lighter, stronger alloys, better medications and longer a shelf life for household products.
Student proposed investigations aboard Skylab, such as web-spinning studies with spiders Arabella and Anita, were performed to compare arachnid behavioral capabilities in microgravity versus on Earth. The spiders proved successful over time, adapting to their environment. Today’s students are bringing forth new innovative ideas and experiments expanding on these biology questions, for instance the YouTube Space Lab investigation to see how jumping spiders adapt to capturing prey in microgravity.
Skylab’s success can be attributed not only to the nine astronauts who made up the rotating crew, but also to the many ground-based teams who worked vigorously during the program. The Skylab Program provided knowledge key to the design and operation of our current orbiting laboratory. "The [International] Space Station was built around what we learned on Skylab," said astronaut Kevin Ford. "What they put up there for us, the way the modules were sized and the way they were constructed in space ... that all came out of what we learned from Skylab."
The investigations performed aboard Skylab, much like the work performed on today’s space station, will continue to help extend our reach farther into the solar system. "We may have done it first, but these guys are doing it better," added Gerald Carr, commander of Skylab 4, echoing Ford’s comments. "People need to continue to do it better and better because we learn more and more as we do this. We just took the first step, and the rest of the steps…are being taken right now."
Happy anniversary, Skylab. Thank you for the paving the way from your friends in the International Space Station Program.