Teams of astronauts spent more than 171 days in Earth orbit aboard Skylab, the first US space station. Launched in 1973, the Skylab mission proved that humans could spend extended periods in space and improved our understanding of the Sun.
Although the mission initially suffered from a launch-damaged thermal shield, more than 120,000 detailed photographs of the Sun were taken by the three crews that visited the station before it re-entered the Earth's atmosphere and broke apart in 1979.
Photo: Scientist-astronaut Edward Gibson outside the Skylab space station (NASA)
Crews on the first US space station study the Sun.
Astronauts see solar flares and coronal mass ejections in great detail.
Following in the steps of Sun observers such as Galileo and Angelo Secchi, US astronauts aboard the Skylab space station captured more than 160,000 images of the Sun. They saw events such as solar flares and coronal mass ejections in great detail. Skylab was launched in 1973.
The first solar space laboratory in orbit loses its heat shield.
Shortly after launch in 1973, Skylab, the first solar space laboratory, lost its heat shield. Astronauts who visited the orbiting science station had to rig a temporary protective barrier to bring temperatures inside Skylab down to safe levels.
Skylab was a space station launched and operated by NASA and was the United States' first space station. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a mass of 169,950 pounds (77 t). Three manned missions to the station, conducted between 1973 and 1974 using the Apollo Command/Service Module (CSM) atop the smaller Saturn IB, each delivered a three-astronaut crew. On the last two manned missions, an additional Apollo / Saturn IB stood by ready to rescue the crew in orbit if it was needed.
The station was damaged during launch when the micrometeoroid shield separated from the workshop and tore away, taking one of two main solar panel arrays with it and jamming the other one so that it could not deploy. This deprived Skylab of most of its electrical power, and also removed protection from intense solar heating, threatening to make it unusable. The first crew was able to save it in the first in-space major repair, by deploying a replacement heat shade and freeing the jammed solar panels.
Skylab included the Apollo Telescope Mount, which was a multi-spectral solar observatory, Multiple Docking Adapter (with two docking ports), Airlock Module with EVA hatches, and the Orbital Workshop, the main habitable volume. Electrical power came from solar arrays, as well as fuel cells in the docked Apollo CSM. The rear of the station included a large waste tank, propellant tanks for maneuvering jets, and a heat radiator.
Numerous scientific experiments were conducted aboard Skylab during its operational life, and crews were able to confirm the existence of coronal holes in the Sun. The Earth Resources Experiment Package (EREP) was used to view the Earth with sensors that recorded data in the visible, infrared, and microwave spectral regions. Thousands of photographs of Earth were taken, and records for human time spent in orbit were extended. Plans were made to refurbish and reuse Skylab, using the Space Shuttle to boost its orbit and repair it. However, development of the Shuttle was delayed, and Skylab reentered Earth's atmosphere and disintegrated in 1979, with debris striking portions of Western Australia. Post-Skylab NASA space laboratory projects included Spacelab, Shuttle-Mir, and Space Station Freedom (later merged into the International Space Station).