By Stephanie Dwilson | 2025-04-28

Astronauts at the International Space Station (ISS) are activating new science experiments following the arrival of a SpaceX Dragon cargo capsule carrying 6,700 pounds of science and supplies.

Expedition 73 crew spent their first week together unpacking the SpaceX Dragon cargo craft, which autonomously docked to the Harmony module's space-facing port on April 22.

SpaceX's 32nd commercial resupply services (CRS-32) mission Dragon cargo capsule launched on a SpaceX Falcon 9 rocket at 4:15am in Florida on April 21.

It carried food, equipment and supplies for the crew aboard the ISS, including:

• An enhanced air quality monitoring system that could potentially help missions to the Moon and Mars.
• An experimental device that distinguishes between smoke and dust in order to reduce false alarms on the space station.
• Two atomic clocks for relativity and global synchronization studies in space.
• An experimental vision-based sensor that could ultimately help improve accuracy for remotely operating robots on the surface of the Moon or Mars.
• An experiment using special nanomaterials that may reduce joint inflammation, help regenerate cartilage lost to arthritis and allow for better drug therapy delivery in space.
• A next-generation pharmaceutical nanostructures experiment.
• An experiment called Rhodium USAFA NIGHT to help space-grown plants rely less on photosynthesis, thus reducing energy use in space.
• Additional materials for drug and product manufacturing.
• A spare catalytic reactor.
• A hand-held tool that lets crew members reach packages in the back of a food warmer.
• Two spare reducer cylinder assemblies that provide 15 minutes of oxygen to a crew member in case of an emergency.
• An extra thermal expansion device.

Experiments under way

NASA astronaut Jonny Kim entered Dragon shortly after it docked and began unloading critical science experiments for installation and activation, NASA said in a blog post on April 23.

Kim and NASA Flight Engineer Nichole Ayers started by removing research samples from inside Dragon's science freezers and loading them inside ISS science freezers.

Kim then installed the Biofilms experiment containers in a pair of Kubik incubators in the Columbus laboratory module to begin studying antimicrobial surfaces that may keep spacecraft safe.

Next, he photographed genetically modified tomato plants for a new space agriculture experiment studying if crops can grow without photosynthesis in space.

Ayers later joined NASA astronaut Anne McClain to configure the cables they will use when they go on a spacewalk planned for May 1.

Meanwhile, Commander Takuya Onishi of the Japan Aerospace Exploration Agency (JAXA) kicked off the new Cell Gravisensing 3 experiment after removing the research gear from Dragon.

The investigation aims to find treatments for space-caused muscle and bone issues as well as similar conditions on Earth, according to NASA. Astronauts will observe the cells' molecular mechanisms and measure how they respond to microgravity.

This was the Dragon spacecraft's fifth flight; it previously flew the CRS-22, 24, 27 and 30 cargo missions.

The spacecraft will remain at the ISS until May, when it undocks and returns to Earth with critical science cargo and hardware. It will splash down off the coast of California.

When it returns to Earth, the CRS-32 will also bring supplies from the ISS that need repairing, including a high gain antenna feed assembly, a multifiltration bed to improve water quality, a planar reflector assembly and more.

The CRS-32 mission is part of NASA's continuing partnership with private companies to resupply the ISS and build a stronger commercial space industry.