Astronaut omics and the impact of space on the human body at scale

Abstract

Future multi-year crewed planetary missions will motivate advances in aerospace nutrition and telehealth. On Earth, the Human Cell Atlas project aims to spatially map all cell types in the human body. Here, we propose that a parallel Human Cell Space Atlas could serve as an openly available, global resource for space life science research. As humanity becomes increasingly spacefaring, high-resolution omics on orbit could permit an advent of precision spaceflight healthcare. Alongside the scientific potential, we consider the complex ethical, cultural, and legal challenges intrinsic to the human space omics discipline, and how philosophical frameworks may benefit from international perspectives.

Fig. 1. Space Missions.

A Violin plots showing the average time a given astronaut spends in space per mission (calculated as total time in space divided by number of missions) compared to the decade the astronaut first went into space. Astronauts are colored by the number of missions they have been on, and shapes represent astronaut sex (females are triangles and males are circles). The average time spent in space ranged from minutes to one month in the 1960s, and from one day to under six months in the 1970s. In the 1980s through 2000s, the majority of astronauts spent an average of between one week and one month in space per mission, but many astronauts spent more than three months in space. Subsequently, in the 2010s, the majority of astronauts spent an average of over three months in space per mission, whereas in the early 2020 s, there was the widest distribution of average time in space, ranging from ten minutes to six months. B The number of astronauts who have been in space by nationality. Bar plot shows the number of astronauts by the year of their first mission whereas the pie chart shows the percentage of each nation’s contribution. Nations with only one astronaut to ever go to space are colored green (4%), nations with only between two and five astronauts to go to space are colored lime green (3%), and astronauts with multiple nationalities are colored yellow (1%). Data was scraped from supercluster.com on September 20th, 2021. Only astronauts who spent time in space and crossed the Kármán line are displayed.

Fig. 2. Cell space atlas.

Multi-omic experiments, whether on Earth or in space, have a number of complexities when designing and comparing results to other published work. Namely, there are numerous models which could be leveraged to investigate the molecular (omic) changes in different organ systems using different technologies, which can then be processed and analyzed in numerous ways. Further, experiments conducted in space may be more influenced by environmental factors that are either regulated within the craft (such as oxygen) or not (such as radiation). These environmental factors are crucial to understanding results and can drastically vary by experiment. Given these complexities, understanding the environmental factors during a mission and the exact experimental design (including acquiring and analyzing the data), and standardizing them across agencies will be crucial to the development of aerospace multi omic analyses. Further, given the overall cost of these experiments as well as the limited resources to conduct them, this centralized and normalized database, which is accessible to other scientists, can assist our understanding of spaceflight risks, their counter measurements, and monitoring.

Fig. 3. Ethics.

Policies pertaining to the collection, storage, and usage of omics data from consenting astronauts and spaceflight participants would need to be carefully balanced. Thorough discussion amongst international ethicists could ensure that such policies are designed such that they are not so restrictive that they significantly limit the potential for scientific progress and improved occupational healthcare in space, and not so permissible that they expose participants to ethical harms.