SpaceX's CRS-35 cargo flight takes lab-grown brain models to the space station

Two of the four investigations are described with an Earth comparison group: the brain models and the crop plants ^[17]. That arrangement lets a difference be pinned on flight and not on how the samples were prepared. The other two ask different questions. One tests whether a plate reader can detect and measure biomarkers such as antibodies, antigens and proteins ^[10]. The other has astronauts repeatedly sample surfaces to monitor for drug-resistant organisms ^[14].

The crop study asks whether diseases develop faster and more severely in microgravity ^[6]. The brain study carries a softer promise. NASA says it could deepen understanding of how the human brain responds to stress and help lay groundwork for methods that counter risks on future missions to the Moon and beyond ^[5]. The thing this doesn't tell you is whether a cell-level change in a tissue model predicts anything about an astronaut's cognition. We think that gap is the main limit on treating the result as crew-health data.

The plate reader targets a delay. It would let scientists analyze samples aboard the station and get data quickly instead of waiting for the samples to return to Earth ^[11]. We think it is the investigation most likely to change how the station works, provided its readings agree with ground laboratory results.

NASA says the bacterial work could help develop ways to protect astronauts against infection during long-duration missions ^[16] and, on Earth, give insight into how superbugs develop from antibiotic overuse ^[15]. NASA's descriptions did not disclose sample counts, the crop species or fungus used, how many surfaces are swabbed, or how plate-reader results will be checked against ground laboratory results.