Pettit, accompanied by cosmonauts Alexey Ovchinin and Ivan Vagner, will launch to the orbiting laboratory in September 2024. In preparation for his fourth spaceflight, read about previous "science of opportunity" experiments Pettit performed during his free time with materials readily available to the crew or included in his personal kit.

Freezing ice in space

Have you ever noticed a white bubble inside the ice in your ice tray at home? This is trapped air that accumulates in one area due to gravity. Pettit took this knowledge, access to a -90° Celsius freezer aboard the space station, and an open weekend to figure out how water freezes in microgravity compared to on Earth. This photo uses polarized light to show thin frozen water and the visible differences from the ice we typically freeze here on Earth, providing more insight into physics concepts in microgravity.

Space cup

Microgravity affects even the most mundane tasks, like sipping your morning tea. Typically, crews drink beverages from a specially sealed bag with a straw. Using an overhead transparency film, Pettit invented the prototype of the Capillary Beverage, or Space Cup. The cup uses surface tension, wetting, and container shape to mimic the role of gravity in drinking on Earth, making drinking beverages in space easier to consume and showing how discoveries aboard station can be used to design new systems.