International Space Station

The International Space Station (ISS) is a special home in space that orbits our planet. It is located in low Earth orbit and is the biggest human-made object that people have ever built in space. Five big space agencies work together to run it: NASA from the United States, Roscosmos from Russia, ESA from Europe, JAXA from Japan, and CSA from Canada.

The ISS is very big — about the size of a football field! It travels around Earth very fast, about 17,200 miles per hour, and completes a whole trip around our planet every 93 minutes. Inside, scientists do many important experiments to learn about living and working in space. People have lived on the ISS since November 2, 2000, making it the place where humans have spent the most time continuously in space.

The station has many parts, including special rooms for the crew to live, work, and do research. It also has big solar panels that give it power and helps it stay cool. The ISS shows how countries can work together to achieve amazing things in space. In the future, some parts of the ISS may be used for new space stations, and scientists are planning to keep using it until at least the end of 2030.

Conception

The International Space Station (ISS) is a special home for astronauts orbiting Earth. It was built and is run by five space agencies from different countries: NASA from the United States, Roscosmos from Russia, ESA from Europe, JAXA from Japan, and CSA from Canada. This station is the first one made by many countries working together, and it is the biggest spacecraft humans have ever built.

Purpose

The International Space Station (ISS) was built to act as a laboratory, observatory, and factory in space. It also helps prepare for future trips to places like the Moon and Mars. Over time, its roles grew to include commercial, diplomatic, and educational work.

The ISS is a special place for scientific research. It has power, data, and people to help scientists run experiments. Research there looks at many topics, like space biology, astronomy, and how the human body changes in space. One famous experiment is the Alpha Magnetic Spectrometer, which searches for dark matter. The space environment is very harsh, but some tiny life forms can survive there. Studies on the ISS help us understand how space affects humans, which is important for future trips to faraway places like Mars. Scientists also use the ISS to watch Earth and study the Sun and stars.

International co-operation

The International Space Station is a huge project in space that many countries worked on together. It includes five space agencies from the United States, Russia, Europe, Japan, and Canada. These countries made agreements to share ideas and help each other build and use the space station.

Even though Brazil wanted to join, they couldn’t finish their part because of money problems. Because of this, Brazil left the project in 2007. Later, when there were big problems between Russia and other countries, some people worried that Russia might stop working with everyone else. But the space station kept going, with other countries ready to help keep it in space.

Construction

Main article: Manufacture of the International Space Station

Main articles: Assembly of the International Space Station and List of ISS spacewalks

The International Space Station is built through teamwork from countries around the world. Parts were made in different places, such as Russia, the United States, Europe, Japan, and Canada. For example, some pieces were created in Moscow, others in Alabama, and more in Germany and Japan.

Building the station started in 1998. Pieces were sent into space on rockets or space shuttles. Astronauts added new parts using robots or by walking in space. The station grew bigger over time, with many new rooms and tools added. Even when a space shuttle stopped flying in 2003, building continued using other rockets. Today, the station has many parts from many nations, showing how people can work together in space.

Structure

The International Space Station (ISS) is a space station in low Earth orbit. It functions as a modular space station, allowing modules to be added or removed for flexibility.

The ISS is made up of many parts, including pressed modules where astronauts live, airlocks for spacewalks, and unpressurized parts that hold equipment. Key modules include Zarya, the first part of the ISS, and Unity, which connects the Russian and U.S. parts. Other important modules are Zvezda, the Russian control center; Destiny, the U.S. research lab; and Kibō, Japan’s research module. The station also has robotic arms and solar arrays to support its operations.

Onboard systems

Life support

Main articles: ISS ECLSS and Chemical oxygen generator

The International Space Station has important systems to keep the air clean, supply water and food, manage waste, and detect fires. The Russian part of the station, called the Zvezda service module, holds many of these life-support systems. The Nauka laboratory also has its own full set of life-support systems.

Atmospheric control systems

The air inside the ISS feels like the air on Earth. The pressure is the same as it is at sea level. The station keeps this air mix using special machines. One machine, called Elektron, makes oxygen by turning water into air and venting out a gas called hydrogen. There are also backup oxygen tanks and special canisters that burn to make more oxygen.

Power and thermal control

Main articles: Electrical system of the International Space Station and External Active Thermal Control System

Big solar panels on the ISS collect sunlight to power the station. These panels can catch sunlight directly and also sunlight that bounces off Earth. The solar panels move to follow the Sun, which helps them collect the most energy.

The station uses special batteries to store energy for when it passes into Earth’s shadow. These batteries were changed in 2016 to newer, longer-lasting ones. The station also has a system to keep its temperature just right. This system uses water and special liquids to move heat away and keep everything comfortable inside.

Communications and computers

Main articles: Tracking and Data Relay Satellite and Luch (satellite)

See also: ThinkPad § Use in space

The ISS uses many radios to talk to mission control centers on Earth and to let crew members talk to each other and to people back home. The station has different radios for different jobs, like talking during spacewalks or when spaceships come and go.

Astronauts use special laptops to help run the station and do their work. These laptops are changed to work with the station’s power and to stay cool in space. There are two types of laptops: one type helps control the station, and the other type is used for everyday tasks like checking instructions, sending emails, or relaxing during free time.

Operations

Each permanent crew on the International Space Station (ISS) is given an expedition number. These expeditions last up to six months, from launch until the crew leaves the station. Initially, crews had three members, but after a space shuttle accident, crews were reduced to two to ensure the station could still operate with fewer supplies. Later, crews grew back to three and then to six members as the station expanded. With the use of commercial spacecraft starting in 2020, the crew size increased to seven, which was the original design.

Some people have spent a lot of time on the ISS. For example, Oleg Kononenko spent nearly 1,111 days in space over several missions. Peggy Whitson spent over 675 days in space, the most of any American.

Orbit, debris and visibility

The International Space Station (ISS) orbits Earth in a nearly circular path at an angle of 51.6 degrees to the equator. This angle was chosen so that Russian spacecraft launched from Baikonur Cosmodrome can reach it without flying over certain areas. The ISS travels at about 28,000 kilometres per hour and completes a full orbit around Earth every 93 minutes.

The ISS orbits at heights between 370 and 460 kilometres above Earth. It moves through an area with space debris, such as old rocket parts and tiny pieces from satellites. To protect the station, special shields are built into its structure. If a piece of debris gets too close, the station can change its orbit slightly to avoid it. Sometimes, the crew must move to their spacecraft if a big piece of debris is coming too close. The ISS can be seen from the ground as a bright moving dot in the night sky, especially around dawn or dusk. Websites and apps can help people know when and where to look to see the ISS.

Environment, safety and crew health

The International Space Station (ISS) has special ways to keep astronauts safe and healthy in space. One big challenge is microgravity—a feeling of weightlessness because objects in orbit are constantly falling around Earth. This can be bumpy because of air movement, machine vibrations, rocket fires, and even small gravity tugs from different parts of the station.

The ISS also faces radiation from the Sun and stars. Earth’s magnetic field helps a lot, but solar storms can still be risky. Astronauts sometimes hide in safer parts of the station during these events. Radiation can hurt cells and increase cancer risk, so the station has shields and special medicine to help.

Other worries include noise from machines and life support systems. Even though it might not sound loud on Earth, astronauts hear it all day, every day, which can tire them out. The space station teams work hard to add quiet covers, sound blockers, and new quiet machines to keep noise down.

Living in such a small space with people from many countries also brings stress. Speaking different languages and adjusting to living without up or down can be tough. Astronauts exercise for at least two hours a day to keep their muscles and bones strong, and they have special equipment like treadmills and weight machines on board. Even though space life is tough, these tools help keep astronauts healthy.

Life aboard

The International Space Station (ISS) has a living space bigger than a six-bedroom house. It includes seven private sleeping areas, three bathrooms, two dining rooms, a gym, and a big window with a 360-degree view.

Crew members follow a daily schedule starting at 06:00 with wake-up and morning checks. They spend about 10 hours working each weekday on exercises, experiments, and station tasks, with shorter workdays on Saturdays. Their free time can include hobbies, family calls, or looking at Earth through the windows. Food on the ISS is specially packaged to stay fresh for long periods and is often seasoned more for taste in space. Crews enjoy fresh foods from resupply missions and sometimes grow their own vegetables, like lettuce and kale, to add to their meals. Personal hygiene is managed with wet wipes and special toilets that collect waste for disposal when cargo leaves the station.

End of mission

The International Space Station was meant to stay in space for 15 years, but it has been extended many times because it has been so successful. Some of the oldest parts have been orbiting Earth for over 25 years.

The United States first planned to stop using the ISS in 2016, but this date was pushed back many times. By 2022, laws were passed to keep the ISS operating until at least 2030. In early 2026, there was a plan to possibly move the ISS to a safe place in space for future use instead of letting it fall back to Earth.

Russia has said it plans to leave the ISS after 2025, but its parts will help keep the station in orbit until 2028. There have also been discussions about what will happen to the ISS after it stops being used.

End of mission considerations

As the ISS gets older, it has needed more repairs. Astronauts spend much of their time fixing things, and there have been worries about safety because of small leaks and other problems. Keeping the station working costs money, and some think it should be preserved as an important place in space history.

If the ISS is left without repairs, it could break apart and create dangerous pieces of space junk that might hit other satellites or even Earth. Countries that launched parts of the ISS are responsible for making sure this does not happen.

Post mission

NASA looked at different ways to deal with the ISS when it is no longer used. One idea was to let it fall back to Earth randomly, but this could danger people and things on the ground. Another idea was to push it higher in orbit, but this would cost a lot and still could be dangerous. The plan NASA chose is to use a special spacecraft to guide the ISS down in a safe, remote part of the ocean in January 2031. NASA is working with SpaceX to build this spacecraft.

Follow up plans

After the ISS, NASA and other space agencies want private companies to build new space stations. One plan is for a company called Axiom to start with a small part attached to the ISS in 2027 and then build more later. Some people have suggested turning the ISS into a space hotel after it is retired, but NASA has not found any good plans for reusing it yet.

Cost

The International Space Station is one of the most expensive things ever built, costing about US$150 billion by 2010. This money came from many countries: the United States spent $58.7 billion, Russia spent $12 billion, Europe spent $5 billion, Japan spent $5 billion, and Canada spent $2 billion. It also cost a lot to send many spaceships to build it.

Each day that astronauts lived and worked on the station cost around $7.5 million, which is less than older space stations. Today, NASA still spends about US$3 billion each year to keep the station running.

In culture

The International Space Station (ISS) stands as a symbol of human teamwork and scientific progress. It shows how countries can work together for big goals, rather than competing.

The ISS has been part of many movies, TV shows, and books. Some films, like Space Station 3D and A Beautiful Planet, show the station up close. Others, such as Gravity and Life, use the ISS in their stories. In 2022, a movie called The Challenge (Doctor's House Call) was even filmed on the real ISS, making it the first time actors and a director worked together in space for a film.

The ISS has also appeared in video games. For example, in Call of Duty: Modern Warfare 2, players see the ISS destroyed during a mission. In Far Cry New Dawn, the station appears as a place players can explore after it falls to Earth.