How quickly do living organisms begin to react to spaceflight? Researchers from the University of Florida tried to find the answer to this question. They conducted an experiment on Blue Origin's commercial suborbital New Shepard spacecraft on August 29, 2024. The results were published in the journal npj Microgravity.
The flight included astronaut-biologist Rob Ferl. He brought with him dozens of thale cress (Arabidopsis) plants, a small flower often used in laboratory experiments. The plants were in special tubes attached to his spacesuit. The tubes were activated at four moments: before launch, upon entering weightlessness, at the end of weightlessness before descent, and after landing. Inside each tube was a fixative solution that instantly stopped processes in the cells, so scientists could see what was happening to the plant at a specific second.
On Earth, colleagues Anna-Lisa Paul and Jordan Callaham simultaneously activated control tubes containing the same kind of plants. This made it possible to compare the space samples with the Earth samples and track how the response changed from stage to stage.
It turned out that during the flight, the activity of more than 1,200 genes changed. Moreover, these changes differed in leaves and roots, as well as at different phases of the mission. Many of the affected genes are associated with the response to stress and changing environmental conditions. According to the researchers, adaptation to space is not a single adjustment after arriving in orbit but a gradual process: the organism responds differently to launch, weightlessness, descent and return.
The ability to preserve samples at several points in the flight allowed scientists to see the transition itself, rather than simply compare plants on Earth with those that had already spent time in space, Paul explained.
In addition to biological data, the mission showed that a scientist can conduct an experiment in flight himself, without relying only on automation or specially trained astronauts. Ferl monitored the operation of the tubes, checked that the solution fully covered the samples, and recorded the time and quality of each sample. He set out his arguments in favor of this approach in a separate column in the same issue of the journal.
The work has limitations: it involves a single flight and a limited set of samples. The authors emphasize that suborbital flights are a real scientific platform, but broad conclusions about long-duration spaceflight cannot yet be drawn from these data.