The science that the Crew Dragon astronauts are working on aboard the ISS

Georgina Torbet

NASA’s Bob Behnken and Doug Hurley made history last week when they became the first astronauts to be launched from U.S. soil in nearly a decade, on the first crewed test flight of SpaceX’s Crew Dragon capsule. They arrived safely at the International Space Station (ISS) 19 hours later. But they aren’t resting or vacationing on the space station — they’re already being put to work on the ISS’s variety of science experiments.

One of their first jobs was to disassemble the station’s Advanced Plant Habitat, an enclosed, automated habitat used for plant bioscience research. The habitat’s environmental control system needs some maintenance work so it can continue to control factors including temperature, relative humidity, carbon dioxide level, light intensity, and spectral quality, allowing experiments on plants to run for up to 135 days.

They also worked on the Electrolytic Gas Evolution Under Microgravity experiment, which looks at how bubbles grow and form during the electrolysis of water in low-gravity environments. This has applications for the production of oxygen on the space station and other space environments like the moon and Mars, and also has applications on Earth, for developing ways to deliver medical drugs through skin patches.

The International Space Station’s two newest crew members, NASA astronauts (from left) Bob Behnken and Doug Hurley, are pictured having just entered the orbiting lab shortly after arriving aboard the SpaceX Crew Dragon spacecraft. NASA

The drug delivery project aims to make a pump which is smaller and more discrete than currently available options, by using a flexible bandage-like pump which infuses drugs directly into the skin instead of requiring an injection. This research is being done on the space station instead of on Earth because the microgravity environment makes it easier to study the precise way that fluids behave, in a field called microfluidics.

The pump design uses electrolysis, meaning the use of an electric current to induce a chemical change. And this process creates bubbles, which change the pressure within the pump to “push” drugs in a precise way. That’s why the astronauts on the ISS are looking at the formation of bubbles in microgravity.

The other astronauts aboard the ISS, NASA’s Chris Cassidy and Roscosmos’s Anatoly Ivanishin and Ivan Vagner, are also busy as ever with projects including the servicing of spacesuits ahead of spacewalks planned for later this month and swapping out fuel bottles for an experiment into preventing spacecraft fires.