After Artemis II, what are the biggest unanswered questions about human health before Artemis III?
At its core, Artemis II was a systems test of the life support and engineering capabilities needed to sustain a human crew, and those systems performed as expected or better. Looking ahead, one of the next major questions is how the Human Landing System vehicles, being developed by SpaceX and Blue Origin, will perform and ensure crew safety on the lunar surface.
How does planning for longer, deeper space missions change the way we think about medical care and risk?
Long-duration missions far from Earth significantly complicate medical care, and risk increases accordingly. In low Earth orbit, astronauts have continuous support from mission control, with options for resupply or even medical evacuation. Beyond that, those safety nets disappear. Crews traveling to the moon or Mars will need to operate with far greater independence, limited resources and no immediate evacuation options. That means developing more capable onboard medical systems and training astronauts to manage a wider range of conditions.
What does “medical autonomy” look like for astronauts operating farther from Earth?
A key concept is Earth-independent medical operations, or EIMO. It represents a shift in decision-making from ground-based flight surgeons to the crew. On the International Space Station, astronauts still rely heavily on support from Earth, but that becomes less feasible as distance and communication delays increase. Future crews will need to diagnose and manage medical issues more independently. Missions to the moon are an important steppingstone toward the level of autonomy required for Mars.
How might longer missions reshape what we know about the cardiovascular system and immune response?
We know spaceflight affects both systems, but the long-term clinical implications remain unclear. Astronauts experience changes in blood volume and cardiovascular adaptation, and the immune system appears to be suppressed. The longest continuous human spaceflight has been just over a year, so missions lasting multiple years will push into largely uncharted territory.
What new questions are emerging about brain function and cognitive performance?
Astronauts are among the highest-performing individuals on the planet, and their cognitive function has been studied extensively. So far, the effects of spaceflight appear minimal and similar to what we see in other isolated and confined environments. However, important questions remain about the long-term neurological impact of deep-space missions, and those answers will likely come from longer-duration exploration.
How do extended isolation and delayed communication reshape what we know about mental health in space?
Psychological stress is one of the most significant challenges in deep space. Humans did not evolve to live in confined environments with a small number of people for months or years at a time. Astronauts undergo extensive screening and resilience training, but even small behaviors can become sources of tension over time. Analog studies on Earth show patterns of burnout, loneliness and depression, and many of those findings are already informing how crews are prepared.
As missions go deeper into space, how does radiation exposure affect cancer risk?
Radiation exposure is substantially higher outside Earth’s atmosphere, which increases cancer risk for astronauts. That risk depends on both environmental exposure and individual genetics. Ongoing research is focused on protecting crews and understanding how radiation affects tissue and DNA, with implications for cancer prevention more broadly.
Are vision-related changes expected to become more pronounced on longer missions?
Spaceflight can affect vision in several ways, including spaceflight-associated neuro-ocular syndrome (SANS), where changes in the retina can lead to gradually worsening eyesight over time. Prem Subramanian, MD, PhD, professor and chief of neuro-ophthalmology at the University of Colorado Anschutz Department of Ophthalmology, is one of the leading experts studying this issue and has worked with collaborators at CU Boulder to better understand the underlying physiological mechanisms. His team has also conducted research involving commercial SpaceX astronauts, helping expand what we know about how these changes develop and how to protect astronaut vision as mission durations increase.
How are insights from deep space missions helping advance care on Earth?
Many solutions developed for spaceflight translate directly to resource-limited environments on Earth, including rural communities, remote research stations and disaster zones. Technologies like AI-driven clinical decision support and compact medical systems are designed for autonomy and efficiency, making them broadly applicable beyond space exploration.
Space missions don’t always go as planned. What can challenges teach us about designing safer systems?
Large-scale missions like Artemis require constant iteration. Even highly successful missions encounter small issues, such as system malfunctions or environmental control challenges, which teams then work to address. As missions become more complex, these challenges may carry greater consequences. Researchers at CU Anschutz are focused on integrating human health into vehicle design and operations to help identify and mitigate risks early.
.png)
