A JPL facility built to support potential robotic spacecraft missions to frozen ocean worlds helps engineers develop safety tests for next-generation spacesuits.
When NASA astronauts return to the Moon under the Artemis campaign and eventually venture farther into the solar system, they will encounter conditions harsher than any humans have experienced before. Ensuring next-generation spacesuits protect astronauts requires new varieties of tests, and a one-of-a-kind chamber called CITADEL (Cryogenic Ice Testing, Acquisition Development, and Excavation Laboratory) at NASA’s Jet Propulsion Laboratory in Southern California is helping.
Built to prepare potential robotic explorers for the frosty, low-pressure conditions on ocean worlds like Jupiter’s frozen moon Europa, CITADEL also can evaluate how spacesuit gloves and boots hold up in extraordinary cold. Spearheaded by the NASA Engineering and Safety Center, a glove testing campaign in CITADEL ran from October 2023 to March 2024. Boot testing, initiated by the Extravehicular Activity and Human Surface Mobility Program at NASA’s Johnson Space Center in Houston, took place from October 2024 to January 2025.
An astronaut boot — part of a NASA lunar spacesuit prototype, the xEMU — is readied for testing in JPL’s CITADEL. A thick aluminum plate stands in for the cold surface of the lunar South Pole, where Artemis III astronauts will confront conditions more extreme than any humans have yet experienced.
NASA/JPL-Caltech
In coming months, the team will adapt CITADEL to test spacesuit elbow joints to evaluate suit fabrics for longevity on the Moon. They’ll incorporate abrasion testing and introduce a simulant for lunar regolith, the loose material that makes up the Moon’s surface, into the chamber for the first time.
“We’ve built space robots at JPL that have gone across the solar system and beyond,” said Danny Green, a mechanical engineer who led the boot testing for JPL. “It’s pretty special to also use our facilities in support of returning astronauts to the Moon.”
Astronauts on the Artemis III mission will explore the Moon’s South Pole, a region of much greater extremes than the equatorial landing sites visited by Apollo-era missions. They’ll spend up to two hours at a time inside craters that may contain ice deposits potentially important to sustaining long-term human presence on the Moon. Called permanently shadowed regions, these intriguing features rank among the coldest locations in the solar system, reaching as low as minus 414 degrees Fahrenheit (minus 248 degrees Celsius). The CITADEL chamber gets close to those temperatures.
About The Author
