NASA’s SpaceX Crew-13 mission to the International Space Station (ISS) is centered on a range of biomedical and human performance studies aimed at improving astronaut health and safety during long-duration space missions. One key focus is the Venous Haemostasis study, a collaboration between NASA and the European Space Agency (ESA) that examines how microgravity affects blood flow and clotting. This research builds on previous studies by combining data from both agencies to better understand how spaceflight influences the body’s circulatory system. By coordinating blood collections and other physiological data, researchers hope to reduce the need for frequent blood draws while gaining more comprehensive insights into how astronauts' blood behaves in space. Throughout the mission, astronauts will undergo a series of tests, including MRI scans, jugular vein ultrasounds, blood pressure checks, and blood draws, both before, during, and after their time on the ISS. These assessments will help track changes in blood composition and flow, which could inform strategies to protect astronauts’ health and improve re-entry procedures. Researchers are also interested in whether findings from this study might lead to better ways of preventing and treating blood clots both in space and on Earth. Another important study, called Manual Piloting, will test astronauts’ ability to handle challenging landing scenarios using simulations similar to those used for lunar landings. This is particularly relevant because long-duration spaceflight can affect sensory systems, making it harder for astronauts to adjust to changes in gravity. Researchers want to determine if refresher training before landing can improve their performance and decision-making during critical moments. In addition to these studies, Crew-13 astronauts will participate in the B-Complex study, which explores whether daily B-vitamin supplements can help prevent Spaceflight-Associated Neuro-ocular Syndrome (SANS), a condition that can alter astronauts’ eye structure. Participants will take B vitamins and undergo vision tests before, during, and after the mission to evaluate the supplement’s effectiveness. The study will also assess how B vitamins affect blood vessel function. The mission also includes three additional studies under NASA’s Human Research Program: Standard Measures, Spacecraft Occupant Risk, and Zero T2. These studies aim to collect baseline data on astronauts’ health, evaluate risks during landing, and compare the effects of exercise routines on astronaut performance. The results of these investigations will contribute to NASA’s broader goal of ensuring astronaut health and safety during future missions, including the Artemis program to return humans to the Moon and eventual journeys to Mars.