Curiosity and the desire to explore are traits deeply rooted in human nature. Space exploration is no exception; it reflects humanity's timeless drive to seek new horizons, challenge our limits, and understand our universe.
The advancements of modern civilization-from the electricity that powers our homes to basic hygienic breakthroughs that ensure our health- happened thanks to humanity's dedication to expanding our knowledge and transforming our world. Similarly, before we can venture into deep space, we must expand our knowledge to understand life beyond Earth. The International Space Station provides the platform for sharpening the skills, technology, and understanding that has springboarded humanity forward, leading us back to the Moon, Mars, and beyond.
In November 2025, NASA and its international partners will surpass 25 years of continuous human presence aboard the International Space Station. As NASA prepares for Artemis missions to the Moon and sets sights on Mars, the space station continues to enable groundbreaking research not possible on Earth, making significant strides in our journey farther into the final frontier.
Step 1: Mastering a New Environment
Space presents an entirely new physical environment with a unique set of challenges. Without Earth's gravity, researchers first needed to master techniques for basic tasks like drinking water, sleeping, exercising, and handling various materials. Fundamental research in the early days of the space station helped us address these basic challenges and move forward to more advanced physics, building multiple space-based research facilities, developing life support systems, and even improving consumer products for life on Earth.
The human body experiences challenges in space like adapting to different gravitational fields and living for long periods in a closed environment. For example, fluid shifts in the body due to microgravity can cause changes with the eyes, brain, bones, muscles, and cardiovascular system. Being able to see, breathe, and function optimally are critical to living and working in space. Research aboard the space station is producing solutions to these challenges and equipping humans for deep space exploration though research like simulating moon landings to clarify how gravitational transitions affect piloting capabilities and decision-making.
Step 2: Creating Self Sufficiency in Space
As missions venture farther from Earth, reliable technologies and self-sustaining ecosystems become essential. The space station provides a testbed to refine these systems before human's travel to distant destinations.
Food, water, and air are among the basic needs for human survival. Thanks to testing aboard the space station, we have developed state-of-the-art life support systems that could be used on future commercial space stations and the Artemis missions. The space station also has enabled testing of evolving technologies to recycle air, water, and waste. In the U.S. segment of space station, NASA achieved 98% water recovery, the ideal level needed for missions beyond low Earth orbit.
Deep space missions could last several years, and astronauts will need enough food to sustain them the entire time. Packaged food can degrade and lose nutrients and vitamins over time, and a deficiency in vitamins can cause health issues. Growing and producing fresh foods and nutrients will be vital during these missions. Over 50 species of plants have been grown aboard the space station, including a variety of vegetables, leafy greens, grains, and legumes. Scientists are testing different systems for scalable crop growth, including aeroponic and hydroponic systems. Research is also being conducted to produce vital nutrients in orbit using microbes.
Researchers have also advanced 3D printing in space, enabling astronauts to make tools and parts on-demand. This ability is especially important in planning for missions to the Moon and Mars because additional supplies cannot quickly be sent from Earth and cargo capacity is limited. Experiments on the space station have made it possible to 3D print plastic parts and tools, and test ways to reuse waste like plastic bags and packing foam as material for 3D printers. In 2024, ESA (European Space Agency) successfully 3D printed the first metal part aboard space station, a step towards more diverse manufacturing during future missions.
Step 3: Preparing for Lunar and Martian Exploration
Before astronauts explore new terrains, we first must collect data and imagery to better characterize the surface of these cosmic destinations. Astronauts aboard the space station have collected photographs to document Earth's surface through Crew Earth Observations. Now, those same techniques are being adapted for Artemis II , where astronauts will use handheld cameras to capture images of the Moon's surface-including the largely unexplored far side. These observations will increase our understanding of the lunar environment and help prepare for exploration missions.
When they land, astronauts will need shelter from radiation, debris, and contaminants. Technology demonstrations aboard the space station tested the packing techniques, protection capabilities, and venting systems of lightweight inflatable habitats. For more permanent structures, space station experiments have studied how concrete hardens in reduced gravity and tested 3D printing nozzles designed to use regolith – the dust present on the Moon and Mars- as material for constructing habitats on-site.
Robotic experiments aboard the space station are demonstrating tasks like moving objects, early detection of equipment issues, 3D sensing, and mapping. Robots could support astronauts during deep space missions by performing routine tasks, responding to hazards, and reducing the need for risky spacewalks.
Analyzing samples though DNA sequencing has historically been expensive and time intensive, limiting its use in space. Advancements have led to DNA processing aboard the space station and refined sequencing techniques. Not only can this ability potentially identify DNA-based life off Earth, but it is necessary for microbial monitoring to keep crews safe and healthy.
Communications is another important component of space exploration. NASA used the space station to demonstrate laser communications capabilities, enabling transmission of more data at faster rates. This communication could serve as a critical two-way link to keep astronauts connected to Earth as they explore deep space.
Step 4: Testing Beyond Low Earth Orbit
Experiments and technologies first tested aboard the space station made their way around the Moon in an uncrewed Orion vehicle during the Artemis I mission. Radiation technology verified on station confirmed that the Orion spacecraft's design protects against harmful exposure. An identical BioSentinel experiment on both space station and Artemis I studied how yeast cells respond to different levels of space radiation.
Additionally, Moon Imagery research calibrated cameras for Orion's navigation systems using photos of the Moon taken from space station, ensuring accurate guidance even if communication with Earth is lost.
Three experiments that landed on the Moon during Firefly Aerospace's Blue Ghost Mission-1 were made possible by earlier research on the space station. These studies help improve space weather monitoring, tested computer recovery from radiation damage, and advanced lunar navigation systems.
Methods used to conduct research on the space station are making their way aboard Artemis II, a mission to place four astronauts in orbit around the Moon. Adapted from human health measurements conducted during space station missions, measurements taken on Artemis II crew will expand a repository of human health data to provide a snapshot of how spaceflight affects the human body beyond low Earth orbit. NASA researchers hope to use this data repository to develop protocols aimed at keeping astronauts healthy on missions to the Moon, Mars, and beyond. Small devices called tissue or organ chips, used for several experiments aboard space station, will continue their scientific journey in the lunar environment. Organ-chip research could improve crew prevention measures and create personalized medical treatments for humans, on Earth and in space.
The International Space Station remains a vital scientific platform, providing the foundation needed to survive and thrive as humanity ventures into the unexplored territories of our universe.
