Much of the research taking place onboard the International Space Station helps doctors improve health for citizens on Earth and astronauts living in space. Other station experiments help engineers design smarter materials and better technologies to advance business and space industries.

At the beginning of the day, British astronaut Tim Peake joined Commander Tim Kopra for blood pressure checks. The duo also checked the fluid pressure in each other’s eyes using a tonometer with support from doctor’s on the ground. The medical checks are part of the ongoing Ocular Health study that seeks to understand vision problems some astronauts have reported after their long-term missions.

Kopra then started researching liquid crystals and their potential for better display screens on spacecraft systems. Afterward, he collected and stored samples for a study that explores how microbes influence the human immune system in space.

Peake spent the rest of the afternoon inspecting the COLBERT treadmill located in the Tranquility module. Veteran cosmonaut Yuri Malenchenko studied radiation exposure before cleaning fans and air ducts inside a pair of Russian modules.