Sunita Williams return | Teamwork makes dream work - The International Space Station story

The International Space Station (ISS) is a global collaboration involving multiple countries. It is the largest structure ever built in space by humans.

Building and Ownership of the ISS

The ISS’s main structure was built between 1998 and 2011, but it continues to evolve with new missions and experiments. Astronauts have been living on board continuously since November 2, 2000. The station is not owned by any single nation but is operated under a cooperative program. Different countries contribute technology, funding, and expertise while sharing the benefits.

WATCH: Why Were Sunita Williams and Butch Wilmore Stuck in Space for 9 Months?

Key contributors include:

• NASA (United States) – Provides modules, technology, and manages operations.
• Roscosmos (Russia) – Supplies rockets, propulsion systems, and life-support equipment.
• ESA, CSA, and JAXA – Contribute laboratory modules, robotic systems, and research.

This teamwork ensures the ISS remains operational, fostering scientific discovery and international cooperation.

Funding and Astronaut Participation

NASA spends $3 billion (₹8,500 crores INR) annually on ISS operations—one-third of its human spaceflight budget. As of May 2024, the ISS has hosted 283 individuals from 22 countries, including astronauts and private participants.

While no astronaut with Indian citizenship has visited the ISS yet, Sunita Williams (of Indian origin) has been a crew member. Group Captain Shubhanshu Shukla of the Indian Air Force is scheduled to fly aboard Axiom Mission 4 in May 2025, marking the first Indian citizen's visit to the ISS.

The United States (163 astronauts) and Russia (57 cosmonauts) have the highest representation in ISS missions. The allocation of astronaut time depends on each country's contributions, including funding, technology, and resources. For example, ESA holds 8.3% of station usage rights, equating to 13 hours of crew time per week.

ISS Partnership and Private Missions

The ISS is a collaborative effort of 15 countries. The primary contributors are NASA (USA), Roscosmos (Russia), ESA (Europe), JAXA (Japan), and CSA (Canada).

Private astronauts have started working on the ISS through companies like Axiom Space, while nations such as the UAE occasionally send astronauts.

The ISS is approved for operations until 2030. However, Russia has announced plans to withdraw after 2024 to focus on building its own Russian Orbital Space Station by 2028.

What happens after 2030 remains uncertain. The ISS might be deorbited or repurposed for future commercial space stations.

Size and Structure of the ISS

• Size: 356 feet (109 meters) end-to-end.
• Mass: 925,335 pounds (419,725 kg) (without visiting vehicles).
• Solar Panels: Cover one acre.
• Habitable Volume: 13,696 cubic feet for crew members.
• Facilities: 7 sleeping areas, 2 bathrooms, a gym, and the Cupola, offering a 360-degree view of Earth.

ISS Orbit and Visibility

• Altitude: 250 miles (402 km) above Earth.
• Orbit Speed: 17,500 mph (28,000 km/h) (completing one orbit every 90 minutes).
• Daily Distance Covered: Equivalent to a round trip between Earth and the Moon.
• Visibility: At dusk or dawn, the ISS appears as a bright moving point in the sky, often as bright as Venus.

How Astronauts Travel to the ISS

Astronauts reach the ISS using SpaceX's Crew Dragon or Russia’s Soyuz spacecraft. 

Before 2011, NASA’s Space Shuttle program was the primary transportation system. After it ended, Soyuz became the only option until SpaceX’s Crew Dragon began missions in 2020.

Boeing’s Starliner is another spacecraft in development but has faced delays, including setbacks during Sunita Williams' mission.

What Astronauts Do on the ISS

Astronauts stay on the ISS for around six months, conducting scientific research, station maintenance, and spacewalks. They also:

• Exercise 2 hours daily to stay fit in microgravity.
• Conduct educational and media outreach events.
• Share experiences via social media.

During short visits, astronauts may sleep inside their spacecraft or find a spare spot on the station, always tethering themselves to prevent floating.

ISS Maintenance and Repairs

Astronauts are responsible for both research and station upkeep. Sometimes, urgent repairs are needed—such as fixing the ammonia cooling system, which prevents the station from overheating.

Also read: Lessons from Sunita Williams’ Extended Mission: Shaping the Future of Space Exploration

Russia’s Role in the ISS

Russia has been a key partner, but relations changed after its invasion of Ukraine in February 2022. Many space partnerships dissolved, yet NASA and Roscosmos continue to operate the ISS together for now.

The ISS is interdependent, meaning it cannot be divided into separate U.S. and Russian sections. The U.S. provides power, while Russia controls propulsion. NASA is testing whether U.S. spacecraft can handle orbital adjustments independently.

The International Space Station (ISS) remains a symbol of global cooperation, advancing science, technology, and space exploration. Whether the ISS is deorbited, repurposed, or replaced by commercial space stations, its legacy as humanity’s longest-running space habitat will continue to inspire future generations.

(Girish Linganna is an award-winning Science Writer, Defence, Aerospace, & Political Analyst, and the Director of ADD Engineering Components India Pvt. Ltd., a subsidiary of ADD Engineering GmbH, Germany. He can be reached at: girishlinganna@gmail.com)