system to favorably respond to invading pathogens and, at the same time, minimize the development of autoimmune diseases. All of this occurs under the influence of gravity on Earth. However, when exposed to microgravity, the human microbiome is altered 4 and such perturbation of the microbiome may have potentially deleterious consequences. 5
On April 24, 2024, “colonizing Mars” yielded about 930,000 results as a Google search term, and NASA, along with various companies such as SpaceX and the Mars One Foundation, are seeking volunteers for such a one-way mission