We are grateful for the opportunity to respond to the recently submitted commentary engaging with our review article, Medical Ethics of Long-Duration Spaceflight. Scholarly critique is an essential part of developing sound ethical frameworks in this nascent and rapidly evolving field. We offer this reply to clarify several philosophical misinterpretations and respond to critiques that, in our view, reflect a misunderstanding of both our intentions and the scope of our article.

Given the increasing involvement of female astronauts in advancing our knowledge of human capacity for long-duration spaceflight, it is critical to determine how to ensure their health and safety, as well as optimize their performance. This commentary discusses the priority to leverage the strengths of innovative collaborations and scientific approaches to enable the identification of potential risks and establish effective countermeasures that will ultimately support the success of space exploration.

Private space missions such as Polaris Dawn exemplify the challenges facing the evolving landscape of space exploration. Polaris Dawn involved high-risk groundbreaking elements that included the first commercial spacewalk. Here, we draw attention to the fact that private spaceflights, while exciting, also have potential ramifications on government-sponsored space programs, highlighting the need to think about acceptable risks for such missions in the broader context of US space policy and funding.

Long-duration spaceflight missions are on the rise. However, recent literature suggests that prolonged and deep-space exposure is likely to introduce increased risks for brain health and consequent detriments to performance and well-being. Given up-to-date evidence, we argue that transcranial magnetic stimulation (TMS) is a promising solution for mitigating behavioral and neurocognitive risks associated with long-duration and deep-space missions. We provide support from recent Earth-based applications of TMS and review several advantages it holds over current treatment approaches. Lastly, we highlight some of the needs in the process of applying such technology to the spaceflight environment.

The integration of biology and spacefaring has led to the development of three interrelated fields: Astrobiology, Bioastronautics, and Space Bioprocess Engineering. Astrobiology is concerned with the study of the origin, evolution, distribution, and future of life in the universe, while Bioastronautics focuses on the effects of spaceflight on biological systems, including human physiology and psychology. Space Bioprocess Engineering, on the other hand, deals with the design, deployment, and management of biotechnology for human exploration. This paper highlights the unique contributions of each field and outlines opportunities for biologists to engage in these exciting avenues of research. By providing a clear overview of the major fields of biology and spacefaring, this paper serves as a valuable resource for scientists and researchers interested in exploring the integration of these disciplines.