Buzz
Italian astronaut Samantha Cristoforetti introduced a groundbreaking experience to life aboard the International Space Station: savoring espresso in space. She made history as the first astronaut to use the ISSpresso, a specially designed space coffee machine developed by the Italian Space Agency, Lavazza, and Argotec.
Unlike traditional space drinks consumed from bags with straws, this unique space espresso is served in 3D-printed cups that rely on surface tension to manage the liquid. Researchers from NASA Johnson Space Center, Portland State University, and the Japanese space agency are sharing findings from the Capillary Beverage Experiment at the American Physical Society's annual fluid dynamics meeting in Boston, detailing how these Space Cups have performed in their initial months of use.
The research team notes that astronauts have been particularly thrilled by the enhanced aroma of the coffee, a stark contrast to the experience of drinking through a straw. One astronaut remarked, "This feels almost exactly like drinking coffee on Earth."
Mark Weislogel from Portland State University highlighted the challenges space baristas encounter in a NASA blog earlier this year:
In a typical espresso, carbon dioxide bubbles form and gather to create a layer of crema. Some bubbles stick to the cup's walls, while others rise and separate by size, forming foam layers. Steam rises above the crema, partially condensing on the cup's inner surfaces. The cup cools through natural convection, and aromatics disperse based on buoyancy. All these processes are driven by gravity!
The Space Cup works by creating a capillary connection when you touch your lips to it, similar to how a paper towel absorbs water, drawing the liquid into your mouth. In microgravity, liquids flow along sharp edges, so the cup's interior corner directs the espresso toward your mouth.
The insights from fluid dynamics research using these Space Cups could influence the design of other fluid systems on the ISS, such as fuel or water storage.
