The Expedition 59 crew focused intensely on human research today to improve the health of people on Earth and in space. The residents aboard the International Space Station are busy exploring how the human body and other organisms adapt to space helping NASA prepare to go to the moon by 2024.

Astronauts Christina Koch and Anne McClain split Friday checking on the Kidney Cells experiment seeking innovative treatments for kidney stones, osteoporosis and toxic chemical exposures. Counteracting the space-exacerbated symptoms is critical to the success of a long-term spaceflight to the moon and Mars.

McClain started her day with Commander Oleg Kononenko and Flight Engineers Nick Hague and Alexey Ovchinin researching space-caused head and eye pressure. The quartet tested a specialized suit, the Lower Body Negative Pressure suit, that reverses the upward flow of blood and other fluids toward an astronaut’s head. The crewmates also participated in ultrasound scans of their eyes and veins for the long-running Fluid Shifts study.

In addition, a pair of Canadian and Japanese robotic arms on the station are coordinating to swap external payloads over the weekend. Two Earth and space research facilities inside the SpaceX Dragon’s trunk are being removed for installation on the station. An older atmospheric experiment that has completed its mission will be placed back in Dragon’s trunk.

The Canadarm2 robotic arm removed the Orbiting Carbon Observatory-3 (OCO-3) from the Dragon’s unpressurized trunk. It handed off the OCO-3, a global carbon detection device, to Japan’s smaller robotic arm for installation on the Kibo lab module’s external pallet. Next, the Canadarm2 will extract and install the Space Test Program-Houston 6 hardware for space physics research on the station’s truss structure.

Finally, Japan’s robotic arm attached to Kibo will hand off the Cloud-Aerosol Transport System (CATS) to the Canadarm2 for installation in Dragon’s trunk. Before Dragon splashes down in the Pacific at the end of May, its trunk with CATS inside will separate during reentry and burn up over Earth’s atmosphere.

A SpaceX Dragon resupply ship delivered CATS in January of 2015 for robotic installation on Kibo’s external pallet. CATS successfully demonstrated low cost atmospheric monitoring techniques from the station.