Four astronauts who spent three days off Earth in September 2021 underwent significant physical and mental changes, as reported in a collection of papers published in the journal Nature and related journals. These changes included declines in cognitive tests, stressed immune systems, and genetic changes within their cells. Although most of the alterations returned to normal after their return to Earth, these findings shed light on the limited understanding of the effects of space travel on the human body.
Insights from the Inspiration4 mission
The Inspiration4 mission marked a significant milestone as the first trip to orbit where none of the crew members were professional astronauts. Led by billionaire entrepreneur Jared Isaacman, the mission included three travelers from diverse backgrounds: Hayley Arceneaux, a physician assistant and cancer survivor; Sian Proctor, a community college professor; and Christopher Sembroski, an engineer. The crew members consented to participating in medical experiments, which involved collecting various bodily samples such as blood, urine, feces, and saliva during their flight. The data collected was cataloged in an online archive known as the Space Omics and Medical Atlas (SOMA).
Impact on cognitive performance and immune systems
Tests conducted on the Inspiration4 crew members using iPads revealed changes in their cognitive performance during space travel. The astronauts showed slower response times and deficits in visual search and working memory compared to when they took the same tests on the ground. This decline in cognitive performance may be attributed to distractions and the awe-inspiring views of Earth from space.
Additionally, the astronauts’ immune systems were found to be under stress during their time in space, potentially due to the challenges posed by the space environment.
Genetic Changes in Astronauts During Space Travel
Telomere lengthening and shortening
Telomeres, age markers in DNA, were observed to undergo lengthening and subsequent shortening in all four Inspiration4 astronauts. The changes in telomere length indicated that such alterations occur in all astronauts and happen rapidly. This finding is significant as it suggests that the bombardment of radiation in space, rather than weightlessness, is the cause of telomere changes. Similar changes were also observed in people exposed to high altitudes, such as those climbing Mount Everest.
RNA changes in astronauts’ cells
The study also revealed changes in the astronauts’ RNA, which is responsible for translating DNA blueprints into proteins. RNA corresponding to the telomeres exhibited alterations in astronauts, similar to those observed in individuals climbing Mount Everest. These findings suggest a connection between changes in RNA and exposure to radiation, indicating potential shared mechanisms between high-altitude environments and space travel.
Comparison to individuals in high-altitude environments
The observations made during the Inspiration4 mission provided valuable insights into the effects of space travel on the human body. By comparing the changes in astronauts with individuals who have experienced high-altitude environments, researchers can better understand the impact of radiation and weightlessness on the human body.
Furthermore, such comparisons could lead to advancements in treatments tailored to individual astronauts to mitigate the effects of space travel.
Medical Implications of Space Travel
Kidney stone formation risks
Researchers identified molecular changes in the astronauts’ kidneys that may indicate a higher risk of kidney stone formation during longer space missions. While this may not pose a problem during a three-day space trip, it could become a medical crisis during extended missions such as a journey to Mars. The newfound awareness of this risk allows researchers to study preventive measures or develop improved treatments should such issues arise in astronauts.
Cognitive performance in space
The cognitive performance of astronauts during space travel was found to be affected, with slower response times observed in various tests.
However, it is important to note that these differences may not necessarily reflect a true decline in their ability to perform tasks in space. Distractions caused by the awe-inspiring views of Earth may contribute to these variations in performance. The collection and analysis of data on cognitive function in space allows scientists to better understand the impact of space travel on astronauts’ mental abilities.
Data collection and analysis for astronauts’ health
The extensive data collected from the Inspiration4 crew members provides a wealth of information for researchers to analyze. By pooling this data and examining it comprehensively, scientists can identify connections between different changes observed in astronauts. This holistic approach enables a better understanding of the underlying mechanisms and the development of targeted countermeasures to minimize the impact of space travel on astronaut health.
Astronauts’ Return to Earth and Post-Mission Activities
After their return to Earth, the Inspiration4 crew members gradually returned to their pre-spaceflight activities. Hayley Arceneaux resumed working as a physician assistant at St. Jude Children’s Research Hospital, while Sian Proctor continued her role as a community college professor. Christopher Sembroski, on the other hand, now works as an engineer at Blue Origin, the rocket company owned by Jeff Bezos. Despite their return to normalcy, the astronauts remain inspired by their space experience and actively contribute to various domains. Dr. Proctor, for instance, became a science envoy for the United States Department of State, using her global platform to inspire and educate the next generation.
As space travel evolves and more private citizens venture into space, the data collected through initiatives such as SOMA will usher in a new era of understanding. The hope is that the information gathered will lead to tailored treatments and countermeasures suited to the individual needs of astronauts, mitigating the effects of space travel. With these advancements, the future of space exploration holds promise, as the transformation of astronauts’ bodies and minds is further investigated and understood.