The International Space Station (ISS) unites astronauts from diverse nations conducting numerous experiments for a deeper understanding of the universe. Initial approval for the ISS construction came from U.S. President Ronald Reagan in 1984, followed by endorsement from the U.S. Congress.
Designed between 1984 and 1993, the different elements of the ISS began to be built by the U.S., Canada, Japan and European countries in the late 1980s. Like a Lego set, each piece of the ISS was built separately and assembled in space by complex robotic systems and people in spacesuits.
In 1993, Russia was invited to join the redesigned ISS. In 1998, the first parts of the ISS, which was worked on with the international partnership of five space agencies from 15 countries, began to be built.
During this period, the first reusable spacecraft were also developed by the U.S. The main construction of the ISS was completed between 1998 and 2011. It was November 2000 when permanent stays on the station began.
On Nov. 2, 2000, NASA astronaut Bill Shepherd, and cosmonauts Yuri Gidzenko and Sergei Krikalev, became the first crew members to stay on the ISS. The purpose of their four-month mission was to complete the tasks necessary to sustain life on the ISS.
The ISS, which is not used by only one country, is seen as a joint program of Europe, the U.S., Russia, Canada and Japan.
The ISS was created with contributions from NASA, the Russian Roscosmos, the European Space Agency (ESA), the Japan Space Exploration Agency (JAXA) and the Canadian Space Agency (CSA).
The main mission control centers are located in the U.S. and Russia, with several auxiliary control centers in Canada, Japan and Europe.
The station is larger than a six-room house, with six sleeping compartments, two bathrooms, a gym and a round window providing a 360-degree view. Living quarters and laboratories are also among the modules inside the ISS.
For the large modules and other parts of the space station, 42 assembly flights were made, 37 by U.S. spacecraft and five by Russian Proton/Soyuz rockets.
An international crew of seven people live and work on the station, which travels at about 8 kilometers per second. More than seven people can also be present on the station during crew change periods.
The ISS orbits the Earth every 90 minutes. This means that in 24 hours, the ISS orbits the Earth 16 times and sees 16 sunrises and sunsets.
Astronauts and cosmonauts make regular spacewalks to build, develop and maintain the ISS, which travels the equivalent distance of the moon and back in about a day.
The ISS is 1 meter shorter than an American football field at 109 meters long and weighs about 420 tons.
Orbiting about 402 kilometers (249.8 miles) above the Earth, the ISS is four times larger than the Russian space station Mir and five times more than the U.S. Skylab.
Cables about 13 kilometers long connect the entire electrical power system on the ISS, with seven different joints and two arms. The robotic Canadarm2 is used to move all modules, conduct scientific experiments and even carry spacewalking astronauts.
More than 1.5 million lines of flight software code run on 44 computers communicating over 100 data networks that transmit 400,000 signals in the U.S. section of the ISS alone, where systems are controlled by more than 50 computers.
A rotation of the station's eight solar panels provides between 75 and 90 kilowatts of power, while the ISS's Water Recycling System meets the crew's demand for water brought by cargo spacecraft.
The ISS has two different docking ports suitable for Russian and European spacecraft and U.S. spacecraft, in cases where the spacecraft cannot approach the docking bay on its own, the robotic arm of the ISS comes into play.
Thanks to the docking mechanism designed for large 100-ton spacecraft, the spacecraft is pushed toward the ISS and pulled by the mechanism like a train car is connected to a locomotive.
Astronauts, who are usually assigned as pilots within the framework of missions, ensure the docking of spacecraft to the ISS and provide the connection between the vehicle and the station.
The astronauts then make the transition to the ISS, and when they have completed their mission, they can successfully return to Earth by detaching the spacecraft from the ISS.
The number of spacecraft that can dock with the ISS at the same time is eight, and these vehicles can reach the ISS between six hours to three days after launch, depending on the spacecraft and launch location.
