In 2025, NASA and its international partners celebrate 25 years of continuous human presence aboard the International Space Station. Since November 2, 2000, more than 290 people from 26 countries have lived and worked aboard the orbiting laboratory, conducting thousands of experiments that have advanced science and technology on Earth and paved the way for Artemis missions to the Moon and future journeys to Mars.
Beyond its role as a science platform, the station has been a bridge—connecting cultures, sparking creativity, and inspiring generations. The memories of Johnson Space Center employees reflect how the orbiting laboratory is not only an engineering marvel but also a deeply human endeavor.
Christopher Brown – Advancing Life Support Systems for Future Exploration
As a space station Environmental Control and Life Support System (ECLSS) integrator, Christopher Brown’s role has been ensuring astronauts have clean air and water. ECLSS removes carbon dioxide from the air, supplies oxygen for breathing, and recycles wastewater—turning yesterday’s coffee into tomorrow’s coffee. Today, these systems can recover nearly 98% of the water brought to the station.
His proudest memory was commissioning regenerative life support systems and raising a symbolic toast with the crew while on console in mission control. He also helped activate the Water Storage System, saving crew time and improving operations on station. For Brown, these milestones were vital steps toward future long-duration missions beyond Earth.
Stephanie Sipila – The Heart of Microgravity Research
Stephanie Sipila, now integration manager for NASA’s Extravehicular Activity and Human Surface Mobility Program, began her career as a mechanical and robotic systems instructor for the orbital outpost. Her favorite experiment, Engineered Heart Tissues, studies microgravity’s effect on the human heart to help develop new treatments for cardiovascular disease. She recalls NASA astronaut Sunita Williams running the Boston Marathon on a treadmill aboard station, becoming the first person to complete the race in space and showing how astronauts stay connected to Earth while living on orbit.
Sipila also highlights the Spacesuit Art Project, an initiative that turned artwork from children with cancer into spacesuits flown to and worn aboard the orbital outpost during live downlinks, connecting science, art, and hope — and raising awareness of cancer research conducted aboard the orbital outpost.
Liz Warren – Where Exploration Meets Humanity
Space station Associate Chief Scientist Liz Warren has seen firsthand how the Spacesuit Art Project uplifted children on Earth. During Expedition 52, she watched astronaut Jack Fischer wear a suit covered in artwork created by young cancer patients, including his own daughter, a survivor. “It was incredibly touching to note the power of art and inspiration. Human spaceflight requires fortitude, resilience, and teamwork—so does fighting childhood cancer,” Warren said.
Her memories also extend to her time as an operations lead for NASA’s Human Research Program, which uses research to develop methods to protect the health and performance of astronauts in space to prepare for long-duration missions. While out for a weekend run, Warren received a call from the Payload Operations and Integration Center in Huntsville, Alabama. An astronaut on station, following a prescribed diet for a research study, wanted to swap out a food item. Warren coordinated with her support team and relayed the decision back to orbit—all while continuing her run. The moment, she recalls, underscored the constant, real-time connection between astronauts in space and teams on the ground.
Adam Baker – Checkmate: Space Debris Cleanup
As an aerospace engineer, Adam Baker helped track experiments and spacecraft operations from mission control. Baker remembers when mission control played a live chess match with astronaut Greg Chamitoff during Expedition 17, a moment that showed the unique ways the station connects crews in orbit with people on Earth. His favorite technical project, though, was the RemoveDebris small satellite, deployed from the station in 2018 to test technologies for cleaning up space junk. “Knowing these experiments could one day help keep the orbital environment safe made it even more meaningful,” he said.
Michael McFarlane – Training for Success
As chief of the Simulation and Graphics Branch, Michael McFarlane prepared astronauts for space station assembly missions using high-fidelity simulators. “My greatest memory is seeing the station grow as we successfully executed assembly missions that looked very much like what we analyzed and trained for in our ground-based simulations,” he said.
A Legacy of Ingenuity and Community
In the Mission Evaluation Room, engineers not only troubleshoot in real time but also celebrate milestones with traditions like “MERloween,” where controllers dress in space-themed costumes to honor the year’s lessons learned.
For social media consultant Mark Garcia, sharing the station story with the public has been the highlight of his career. His favorite moment was watching NASA’s SpaceX Crew-9 splash down in 2025, greeted by dolphins in the Gulf of America. “I love writing about the science aboard the station that benefits people on Earth,” he said.
For 25 years, the International Space Station has shown what humanity can accomplish together. The lessons learned aboard will guide Artemis missions to the Moon and future journeys to Mars—ensuring the next 25 years are built on innovation, resilience, and the human spirit.