Mir, the ISS, and Skylab
A space station is a building or craft that orbits the Earth. To create something like gravity, it rotates while orbiting the Earth. There have been three different space stations since 1973 and in this section you will learn about them all.
There are several reasons to build a space station. Stations have many uses and can be very helpful when conducting experiments. Some experiments are difficult to conduct on Earth, where there is air and other elements that are absent in space. But in a space station, some experiments can be conducted better then they can be done on Earth. For example, welding is easier when completed in a place with no air. Space is an ideal place for welding because it does not have any air in it.
The Skylab was the first space station to be put into orbit. It was launched in1973 and was crewed by three crews until 1974. While on the station the crews conducted several experiments such as measuring the Earth and Sun. In 1979 the space station’s orbit lost strength and eventually the station fell low enough that it burned up in our atmosphere.
Mir: The First Space Station
NASA, Public domain (link).
However that was not the last Earth had seen of space stations. In 1993 the Russian Space Agency began planning with NASA to combine the Russian Mir and the USA Freedom into a single station called Mir. This was a good opportunity for the two great superpowers to act together after the Cold War. Still, Mir was only a preparation step to prepare for an even larger station called the International Space Station, (ISS).
When Mir was finally completed, it was set to work immediately. The Mir Docking Module was invented to help space crafts like the shuttle Atlantis dock easier. In 1995 seven astronauts from the USA lived temporarily—for 28 months!—on Mir. During this time, many small disasters struck the station, including a small fire. Several space walks were needed to restore nearly full power to Mir.
Some skeptical people in the U.S. Congress and in NASA thought it wise to end the Mir program. They thought it risky for the astronaut’s lives, but it was decided that the project continue. In the last few years of Mir’s time in orbit there were many offers to buy it for commercial business. Two Russian crew members attempted to restore Mir to perfect condition. But despite their efforts, Mir was de-orbited in 2001.
ISS: International Space Station
NASA, Public domain (link).
Mir was replaced by the International Space Station (ISS), the current station in space. The ISS is about the size of a football field and weighs approximately 450 tons. It is used to conduct many experiments that have supplied lots of data for many causes. After Mir was launched, work on the ISS was started immediately. The first parts of the station were put into orbit in 1998, three years before Mir was de-orbited. Even today, bits and pieces are still being added to the ISS. For example, the shuttle Discovery in March 2008 carried to the station the European lab, Columbus. Columbus will be the first permanently crewed lab. There are still many more modules to be added to the current ISS…and who knows? There may still be many more space stations to come.