What was Skylab, and who operated it?

Skylab was the United States' first space station, launched and operated by NASA. It served as a vital platform for scientific research and experimentation in orbit.

When was Skylab launched, and for how long was it occupied by astronaut crews?

Skylab was launched on May 14, 1973. It was occupied by three astronaut crews for a total of approximately 24 weeks, with the missions occurring between May 1973 and February 1974.

What was Skylab constructed from, and what did it replace during launch?

Skylab was constructed from a repurposed third stage of the Saturn V rocket, specifically the S-IVB stage. This stage took the place of the S-IVB during the launch.

What were the primary functions and operations conducted on Skylab?

Skylab functioned as an orbital workshop, a solar observatory, and a platform for Earth observation. Astronauts conducted hundreds of experiments covering various scientific disciplines.

When did Skylab re-enter Earth's atmosphere, and where did its debris land?

Skylab's orbit decayed, and it disintegrated in the atmosphere on July 11, 1979. Its debris scattered across the Indian Ocean and Western Australia.

What distinction does Skylab hold among US space stations as of 2025?

As of 2025, Skylab remains the only space station exclusively operated by the United States. Future permanent stations were planned but later shifted focus to international collaboration.

What were the main components of Skylab?

Skylab's main components included the Orbital Workshop (the primary living and working space), the Apollo Telescope Mount (a solar observatory), a Multiple Docking Adapter, and an Airlock Module with extravehicular activity (EVA) hatches.

How was Skylab launched into low Earth orbit?

Skylab was launched into low Earth orbit by a modified Saturn V rocket, designated AS-513. This was the final flight for a Saturn V rocket, which was famously used for the Apollo Moon landing missions.

What critical damage did Skylab sustain during its launch and deployment?

During launch and deployment, Skylab sustained critical damage: its micrometeoroid shield tore away, taking one main solar panel array with it, and jamming the other. This significantly reduced its electrical power and protection from solar heating.

How did the first crew manage to save Skylab after the launch damage?

The first crew (Skylab 2) performed extensive repairs, including deploying a parasol-like sunshade through an instrument port from inside the station to lower temperatures, and freeing the jammed solar panels. This was the first time a repair of such magnitude was performed in space.

What advancements did the Apollo Telescope Mount (ATM) make in solar science?

The Apollo Telescope Mount significantly advanced solar science by providing unprecedented observations of the Sun. It captured thousands of photographs and collected data that confirmed the existence of the Sun's coronal holes.

How did Skylab extend the record for human time spent in orbit?

Skylab missions extended the record for human time spent in orbit. The Skylab 4 crew set a new record of 84 days, surpassing the previous record of 23 days set by the Soyuz 11 crew.

What was Wernher von Braun's vision for a space station in the 1950s?

Wernher von Braun envisioned a large, rotating space station, approximately 250 feet in diameter, that would generate artificial gravity. He saw it as a crucial step for future expeditions to the Moon and Mars, requiring extensive shuttle support for construction.

What was the Manned Orbital Laboratory (MOL) program, and how did it relate to NASA's plans?

The Manned Orbital Laboratory (MOL) was a space station program primarily intended for photo reconnaissance by the Department of Defense. MOL competed for funding with NASA's station plans for several years and influenced NASA's design choices to differentiate them.

What was the "wet workshop" concept, and how did it differ from the final Skylab design?

The "wet workshop" concept involved converting an active fuel tank, like the S-II or S-IVB stage of a Saturn rocket, into a living space after venting residual fuel. This differed from the final Skylab design, which used a "dry workshop" where the interior was pre-prepared before launch, simplifying the process.

What considerations were made for astronaut habitability and comfort on Skylab?

For habitability, designers emphasized comfort by including a wardroom for meals and relaxation, private sleeping quarters, a shower, and a toilet. Astronauts also had access to entertainment options and personal music choices.

How was food quality improved for Skylab missions compared to previous Apollo missions?

Skylab food was significantly improved by prioritizing palatability over strict scientific needs, addressing complaints from earlier Apollo crews about the blandness and unpleasant form of their meals. The food was designed to be more enjoyable for the longer duration missions.

What features were included for astronaut sleeping quarters and personal hygiene on Skylab?

Each astronaut had a private sleeping area comparable to a walk-in closet, complete with a sleeping bag and locker. Skylab also featured a zero-gravity shower system and a specialized toilet designed to collect precise waste samples for study.

What was the designation of the Saturn V rocket used to launch Skylab?

The Saturn V rocket used to launch Skylab was designated SA-513. This rocket was originally produced for the Apollo program before several planned missions were canceled.

What was the mission computer system used on Skylab?

Skylab was controlled by a digital computer system that included two computers (primary and secondary) and a Memory Load Unit (MLU) for program backup. This system was a space-hardened version of the IBM System/4 Pi TC-1 computer.

How many crewed missions visited Skylab, and what were their designations?

Three crewed missions visited Skylab, designated Skylab 2, Skylab 3, and Skylab 4. These missions delivered three-astronaut crews in Apollo command and service modules.

What was the duration of each of the three crewed missions to Skylab?

The three crewed missions had varying durations: Skylab 2 lasted 28 days, Skylab 3 lasted 59 days, and Skylab 4 lasted 84 days.

How many spacewalks (EVAs) were performed in total by Skylab crews, and what was their total duration?

Skylab crews performed a total of ten spacewalks (extravehicular activities or EVAs), accumulating 42 hours and 16 minutes of time outside the station.

What were the main categories of experiments conducted on Skylab?

Experiments on Skylab were divided into six main categories: life science (human physiology, biomedical research), solar physics and astronomy, Earth resources, material science, student research, and studies on human adaptability and habitat operations.

What was the purpose of the Automatically Stabilized Maneuvering Unit (ASMU) tested on Skylab?

The ASMU was tested on Skylab as a technology demonstration to enable astronauts to perform untethered movements in microgravity. Its piloting characteristics helped establish the foundation for later MMU systems used on the Space Shuttle.

For what scientific contribution did Riccardo Giacconi share the Nobel Prize in Physics, involving Skylab?

Riccardo Giacconi shared the 2002 Nobel Prize in Physics for his study of X-ray astronomy, which included observing solar emissions aboard Skylab. This work contributed significantly to the establishment of X-ray astronomy as a field.

What measures were taken to protect vulnerable technology, such as film, from radiation on Skylab?

To protect sensitive equipment like film from radiation, Skylab incorporated five film vaults. These vaults, constructed primarily from aluminum, were designed to shield the film from the harsh space environment.

What types of gyroscopes were used on Skylab, and what were their functions?

Skylab utilized two types of gyroscopes: Control Moment Gyroscopes (CMGs) for physically moving and pointing the station, and rate gyroscopes to measure rotation rates and determine orientation. These systems were crucial for maintaining the precise pointing required by the Apollo Telescope Mount.

What was the capacity of the Skylab shower system in terms of water usage per shower?

The Skylab shower system was designed to use approximately 6 pints (2.8 liters) of water per shower, drawn from a dedicated personal hygiene water tank.

What types of cameras and film were utilized by the Skylab crews for experiments and photography?

Skylab crews used a variety of cameras, including 35mm Nikon and 70mm Hasselblad cameras, a 16mm Maurer Data Acquisition Camera (DAC), and a Polaroid SX-70 instant camera. Various types of film, such as Ektachrome and SO-368, were used.

How was film protected from radiation fogging on Skylab?

Film was stored in specialized film vaults within Skylab to protect it from radiation fogging, which could degrade image quality over the course of the mission.

What was the purpose of the Skylab computer system, and how did it control the station's orientation?

The Skylab computer system was essential for controlling the station's orientation, particularly for pointing the solar power collection systems and observatory instruments. It processed data from various sensors and used gyroscopes and thrusters to maintain the desired attitude.

What personal computing devices were available to Skylab crews?

Skylab crews were equipped with Hewlett Packard HP-35 handheld electronic scientific calculators, which served as their primary personal computing devices, replacing the slide rules used on earlier missions. Some slide rules were also kept onboard for backup.

What was the estimated lifespan of Skylab in orbit after the final crew departed?

After the final crew departed, initial calculations estimated that Skylab would remain in orbit for approximately nine years, with re-entry expected around March 1983.

What were the main challenges or issues that prevented Skylab's reuse?

The primary challenges preventing Skylab's reuse included the failure of one of its three control-moment gyroscopes (CMGs), the inability to repair or replace them in orbit, and the lack of available Saturn V rockets. Delays in the Space Shuttle program also played a role.

What benefits did proponents of Skylab's reuse cite?

Proponents argued that reusing Skylab would provide valuable experience in space construction and maintenance, offer a unique platform for long-duration flight studies, and free up shuttle flights for other purposes. It was also seen as a resource worth hundreds of millions of dollars.

What was the total cost of the Skylab program from 1966 to 1974?

The total cost of the Skylab program from its inception in 1966 to 1974 was approximately US$2.2 billion.

How did the total cost of the Skylab program compare to the cost per man-day on the International Space Station?

With its three crews spending a total of 510 man-days in space, Skylab's cost per man-day was about US$20 million. This is significantly higher than the estimated US$7.5 million per man-day for the International Space Station.

What caused the confusion regarding the numerical designations of the crewed Skylab missions?

Confusion arose because the uncrewed launch was initially designated SL-1, and the crewed missions were planned as SL-2, SL-3, and SL-4. However, some documentation used SLM-1 through SLM-3, and the astronauts ultimately used the 1-2-3 numbering for their mission patches due to pre-manufactured flight clothing.

What was the Skylab Medical Experiment Altitude Test (SMEAT), and what was its purpose?

SMEAT was a 56-day Earth-based test conducted in 1972 that simulated Skylab conditions in a low-pressure, high-oxygen atmosphere but under full gravity. Its purpose was to evaluate medical experiment equipment and gain insights into human adaptation to enclosed environments, with a focus on medical studies.

What was the significance of the McDonnell Douglas Corporation's contract for Skylab?

McDonnell Douglas Corporation received a contract in 1969 for the conversion of two S-IVB stages into Orbital Workshops. This contract was crucial for the physical construction of the Skylab space station.

What was the "Skylab B" station, and what happened to it?

Skylab B was a second, flight-quality backup Skylab station that had been built during the program. NASA decided against launching it due to the high cost and the desire to redirect funds towards the Space Shuttle development. It was later transferred to the National Air and Space Museum.

How did increased solar activity affect Skylab's orbital decay?

Increased solar activity led to greater heating of Earth's upper atmosphere, which in turn increased atmospheric drag on Skylab. This caused its orbit to decay faster than initially predicted, leading to its earlier-than-expected reentry.

What was the public and media reaction to Skylab's impending reentry?

Skylab's reentry became an international media event, with widespread public attention, merchandise like T-shirts, and even wagers on the time and place of its descent. The event caused significant public concern, particularly in countries like the Philippines.

What was the "Skylab Rescue" mission that was on standby?

A "Skylab Rescue" mission was assembled using a backup Saturn IB rocket and Apollo CSM, intended to be on standby in case an in-orbit rescue was needed for the crews. This vehicle was never flown but was also considered for a potential Skylab 5 mission.

What was the "Skylab 5" mission, and why was it cancelled?

Skylab 5 was planned as a short, 20-day mission in April 1974 to conduct more experiments and boost Skylab into a higher orbit using the Apollo Service Propulsion System. It was cancelled, and the associated rocket was put on display at Kennedy Space Center.

What was the total number of days Skylab was occupied by crews?

Skylab was occupied by its three crews for a total of 171 days and 13 hours.

What was the significance of the "wet workshop" concept in Skylab's development?

The "wet workshop" concept was significant because it proposed using an existing, flight-ready rocket stage (like the S-IVB) as the core of the space station, which was a more feasible approach given budget and technological constraints at the time. This idea directly influenced the final Skylab design.

How did the Skylab program contribute to the development of the Space Shuttle program?

Skylab's operations, particularly the extensive repairs performed by astronauts during EVAs, provided valuable experience in space maintenance and repair techniques. This experience was crucial for the development of the Space Shuttle program, which aimed for greater reusability and on-orbit servicing capabilities.

What was the purpose of the Apollo Telescope Mount (ATM)?

The Apollo Telescope Mount (ATM) served as Skylab's multi-spectral solar observatory, equipped with eight telescopes to study the Sun. Its observations significantly advanced solar science and provided data that would have been difficult to obtain with uncrewed spacecraft.

What were the primary materials used in the construction of Skylab's film vaults?

The film vaults on Skylab were constructed primarily from aluminum. The largest vault weighed 2,398 pounds (1,088 kg) empty, while four smaller vaults in the Multiple Docking Adapter had a combined mass of 1,545 pounds (701 kg).

Skylab Wiki: Skylab: Pioneering the Final Frontier

Dive in with Flashcard Learning!

When you are ready...
🎮 Play the Wiki2Web Clarity Challenge Game🎮

Overview

First US Space Station

Skylab, launched by NASA on May 14, 1973, was the United States' inaugural space station. It served as a vital orbital laboratory, occupied by three astronaut crews for a cumulative total of 171 days between May 1973 and February 1974. This pioneering facility significantly advanced our understanding of long-duration spaceflight and human adaptation to microgravity.

Scientific Endeavors

The station was equipped with a sophisticated solar observatory (Apollo Telescope Mount), enabling unprecedented studies of the Sun. It also facilitated extensive Earth observation experiments, capturing valuable data across visible, infrared, and microwave spectra. Numerous life science and physical science investigations were conducted, pushing the boundaries of scientific knowledge.

Legacy and Evolution

Constructed from a repurposed Saturn V third stage, Skylab demonstrated the feasibility of large-scale orbital habitats. Although its orbit eventually decayed, leading to its fiery reentry on July 11, 1979, Skylab's operational successes paved the way for subsequent international collaborations, most notably the International Space Station.

Configuration

Key Dimensions

Skylab's primary structure, the Orbital Workshop, was a repurposed S-IVB stage. The station's total mass in orbit, including the Apollo CSM, was approximately 199,750 pounds (90,610 kg). Its overall length reached 118.5 feet (36.1 meters) with the CSM attached.

The station comprised several key modules, each with specific functions and dimensions:

Component Data
Component	Mass (lb)	Mass (kg)	Volume (ft³)	Volume (m³)	Length (ft)	Length (m)	Diameter (ft)	Diameter (m)
Payload Shroud	25,600	11,600	—	—	56.0	17.1	21.6	6.6
Apollo Telescope Mount	24,500	11,100	—	—	48.1	14.7	11.3	3.4
Multiple Docking Adapter	12,000	5,400	1,140	32	17.3	5.3	10.5	3.2
Airlock Module	49,000	22,000	613	17.4	17.6	5.4	10.5	3.2
Saturn V Instrument Unit	4,600	2,100	—	—	3.0	0.91	21.6	6.6
Total in Orbit	168,750	76,540	12,417	351.6	82.4	25.1	21.6	6.6
Apollo CSM	31,000	14,000	210	5.9	36.1	11.0	12.8	3.9
Total with CSM	199,750	90,610	12,627	357.6	118.5	36.1	21.6	6.6

Power and Atmosphere

Electrical power was supplied by solar arrays and fuel cells within the docked Apollo CSM. The station's atmosphere was maintained at 5.0 psi, composed of 74% oxygen and 26% nitrogen, providing a breathable environment for the crews.

Operations

Launch Damage and Repairs

Skylab's launch on May 14, 1973, was marred by significant damage. The micrometeoroid shield and one solar array were torn away, and the remaining array was jammed. This critical failure severely limited power and thermal control. The first crew, Skylab 2, performed crucial extravehicular activities (EVAs) to deploy a replacement sunshade and free the jammed solar panels, successfully saving the station.

Extended Missions

Three crewed missions visited Skylab: Skylab 2 (28 days), Skylab 3 (59 days), and Skylab 4 (84 days). These missions progressively extended the record for human endurance in space, culminating in the 84-day stay of the Skylab 4 crew. Astronauts conducted ten EVAs, totaling over 42 hours, performing vital repairs and scientific tasks.

Mission Achievements

During its operational life, Skylab logged approximately 2,000 hours of scientific and medical experiments. Astronauts captured thousands of images of the Sun and Earth, contributing significantly to solar physics and Earth resource studies. The station's environment also provided invaluable data on human physiological and psychological adaptation to prolonged microgravity.

Experiments

Life Sciences

Investigations focused on human physiology, including adaptation to microgravity, circadian rhythms, and biomedical research. Experiments also studied the behavior of mice and gnats in space. The crews' own adaptation to the space environment was a primary area of study.

Solar and Stellar Physics

The Apollo Telescope Mount housed eight specialized telescopes for observing the Sun across various spectral bands. Skylab captured detailed images of solar flares and coronal holes, providing data that was crucial for advancing solar physics. Observations of Comet Kohoutek were also conducted during the Skylab 4 mission.

Earth Resources

The Earth Resources Experiment Package (EREP) utilized sensors to record data on Earth's mineral resources, geology, weather patterns (including hurricanes), and land/vegetation. This provided a unique orbital perspective for environmental monitoring and resource management studies.

Material Science & Student Research

Experiments explored processes like welding, brazing, and metal melting in microgravity. Crystal growth and fluid dynamics were also investigated. Notably, Skylab hosted 19 student research proposals, including fascinating studies on spider web construction and human dexterity in space.

Habitability

Zero-G Shower

Skylab featured a unique zero-gravity shower system designed for crew hygiene. It utilized a cylindrical curtain and a vacuum system to manage water droplets, preventing electrical shorts. While functional, the process was time-consuming, and crews often opted for sponge baths.

Improved Cuisine

Recognizing the importance of morale, Skylab's food provisions were significantly improved compared to earlier missions. While still requiring careful management in microgravity, the meals prioritized palatability, offering a more varied and enjoyable diet for the long-duration crews.

Personal Quarters

Each astronaut had a private sleeping compartment, roughly the size of a walk-in closet, equipped with a sleeping bag and locker. This provided a degree of personal space and privacy, crucial for psychological well-being during extended missions. The station's spacious design also included a wardroom for relaxation and dining.

Computers & Control

Core Systems

Skylab was managed by an IBM System/4 Pi computer system (TC-1), a precursor to the Space Shuttle's computers. This system, along with a Memory Load Unit (MLU) for program backup, controlled station orientation, power management, and experimental operations.

Attitude Control

The station utilized control-moment gyroscopes (CMGs) and thruster systems for attitude control and precise pointing of the Apollo Telescope Mount. This sophisticated system allowed Skylab to maintain orientation against disturbances like gravity gradients and aerodynamic drag, crucial for its scientific mission.

User Interface

The primary interface for ground control and astronauts was the Digital Address System (DAS), featuring an octal-based keypad and a display. This system allowed for command input, program changes, and monitoring of station status, demonstrating early forms of spacecraft human-computer interaction.

History

Early Concepts

The idea of a space station evolved from early visions by figures like Wernher von Braun, who initially proposed large, rotating structures. NASA's Apollo Applications Program (AAP) explored various concepts, including "wet workshop" designs utilizing repurposed rocket stages, eventually leading to the S-IVB-based Skylab.

Competition and Funding

Skylab development occurred during a period of budget constraints and competition with the military's Manned Orbital Laboratory (MOL) program. NASA's decision to proceed with the S-IVB-based "dry workshop" design, leveraging available Saturn V hardware, ultimately shaped the station's final configuration.

Transition to ISS

Following Skylab, NASA's focus shifted to the Space Shuttle program and international collaborations. Projects like Spacelab, Shuttle-Mir, and eventually the International Space Station (ISS) built upon the operational and scientific experience gained from Skylab, solidifying its place as a foundational element of human spaceflight history.

Rescue & Re-use

Standby Rescue Missions

To mitigate risks associated with long-duration missions, NASA prepared backup Apollo CSM/Saturn IB vehicles for potential rescue operations. While a rescue mission was assembled for Skylab 4 and the Apollo-Soyuz Test Project (ASTP), it was never required, demonstrating NASA's commitment to crew safety.

Re-boost Plans

Following the final crewed mission, NASA explored options to reboost Skylab's orbit using the Space Shuttle and a Teleoperator Retrieval System (TRS). These plans, aimed at extending the station's operational life and facilitating further research, were ultimately abandoned due to delays in the Shuttle program and the station's inevitable orbital decay.

Controlled Re-entry

Despite efforts to predict and manage its descent, Skylab's reentry on July 11, 1979, scattered debris across Western Australia. While the event garnered significant media attention and public interest, no significant injuries or property damage were reported, marking a relatively safe conclusion to the station's orbital journey.

Teacher's Corner

Edit and Print this course in the Wiki2Web Teacher Studio

Edit and Print Materials from this study in the wiki2web studio

Click here to open the "Skylab" Wiki2Web Studio curriculum kit

Use the free Wiki2web Studio to generate printable flashcards, worksheets, exams, and export your materials as a web page or an interactive game.

True or False?

Test Your Knowledge!

Gamer's Corner

Are you ready for the Wiki2Web Clarity Challenge?

Learn about skylab while playing the wiki2web Clarity Challenge game.

Unlock the mystery image and prove your knowledge by earning trophies. This simple game is addictively fun and is a great way to learn!

Play now

Explore More Topics

Discover other topics to study!

2004 atp tour

kaes van t hof

chalandri

nascar craftsman truck series at bristol

pope zosimus

fast company

olivia rodrigo

malta european parliament constituency

trading post

land use

References

Martin Marietta & Bendix (1978), pp. 1-12 to 1-13.

Martin Marietta & Bendix (1978), pp. 2â9, 10.

Benson & Compton (1983), "8: The Medical Experiments".

A full list of references for this article are available at the Skylab Wikipedia page

Feedback & Support

To report an issue with this page, or to find out ways to support the mission, please click here.

Disclaimer

Important Notice

This page was generated by an Artificial Intelligence and is intended for informational and educational purposes only. The content is based on a snapshot of publicly available data from Wikipedia and may not be entirely accurate, complete, or up-to-date.

This is not professional advice. The information provided on this website is not a substitute for professional consultation regarding space exploration, engineering, or historical accuracy. Always refer to official sources and consult with qualified experts for specific needs.

The creators of this page are not responsible for any errors or omissions, or for any actions taken based on the information provided herein.

Skylab: Pioneering the Final Frontier

💡 Dive in with Flashcard Learning! 💡

Overview 🌌

🛰️ First US Space Station

🔭 Scientific Endeavors

🚀 Legacy and Evolution

Configuration ⚙️

📏 Key Dimensions

⚡ Power and Atmosphere

Operations 🛰️

🛠️ Launch Damage and Repairs

⏳ Extended Missions

📊 Mission Achievements

Experiments 🔬

🧑‍🔬 Life Sciences

☀️ Solar and Stellar Physics

🌍 Earth Resources

🧪 Material Science & Student Research

Habitability 🏠

🚿 Zero-G Shower

🍽️ Improved Cuisine

🛏️ Personal Quarters

Computers & Control 💻

🧠 Core Systems

🧭 Attitude Control

🕹️ User Interface

History 📈

📜 Early Concepts

⚔️ Competition and Funding

➡️ Transition to ISS

Rescue & Re-use 🆘

🚑 Standby Rescue Missions

🔄 Re-boost Plans

💥 Controlled Re-entry

Teacher's Corner 🧑‍🏫

Edit and Print this course in the Wiki2Web Teacher Studio

True or False? 🤔

❓ Test Your Knowledge! ❓

Gamer's Corner 🎮

Are you ready for the Wiki2Web Clarity Challenge?

Explore More Topics

📜 Discover other topics to study!

References

📜 References

Feedback & Support 👍

To report an issue with this page, or to find out ways to support the mission, please click here.

Disclaimer ⚠️

📜 Important Notice

Dive in with Flashcard Learning!

Overview

First US Space Station

Scientific Endeavors

Legacy and Evolution

Configuration

Key Dimensions

Power and Atmosphere

Operations

Launch Damage and Repairs

Extended Missions

Mission Achievements

Experiments

Life Sciences

Solar and Stellar Physics

Earth Resources

Material Science & Student Research

Habitability

Zero-G Shower

Improved Cuisine

Personal Quarters

Computers & Control

Core Systems

Attitude Control

User Interface

History

Early Concepts

Competition and Funding

Transition to ISS

Rescue & Re-use

Standby Rescue Missions

Re-boost Plans

Controlled Re-entry

Teacher's Corner

True or False?

Test Your Knowledge!

Gamer's Corner

Discover other topics to study!

References

Feedback & Support

Disclaimer

Important Notice