A protective vest tested on a manikin during NASA's Artemis I mission could dramatically reduce radiation exposure for astronauts during severe solar storms, according to a new study.
The study, published in the journal Science Advances, reports on the performance of a radiation-shielding vest worn by a female test dummy on NASA's uncrewed Artemis I flight in 2022. This mission, which tested systems for humanity's return to the moon, provides valuable data as NASA works toward establishing a lunar base, where radiation remains a significant threat.
The vest is designed to protect astronauts from the harmful effects of solar storms, which can emit high levels of radiation. By providing shielding, such garments could allow lunar crews to venture beyond their habitats even during these events. A version of the vest has previously undergone testing aboard the International Space Station.
While the vest did not travel with the Artemis II crew due to the mission's short duration and limited space, it may be included in future missions for longer lunar stays. The vest is intended for use during high-radiation events and is designed to cover the most vulnerable human organs and tissues, including the lungs, stomach, bone marrow, breasts, and ovaries. Women are considered particularly susceptible to radiation-induced cancers.
For the Artemis I mission, two life-size female manikins, named Zohar and Helga, were equipped with thousands of radiation sensors and traveled for nearly a month to the moon and back aboard NASA's Orion capsule. Zohar wore the AstroRad vest, a 57-pound (26-kilogram) garment developed by the U.S.-Israeli startup StemRad and Lockheed Martin. Helga flew without the vest but was also equipped with sensors.
Jordan Houri, the study's lead author from StemRad, described the experiment as the largest ever conducted to assess astronaut radiation exposure beyond low-Earth orbit. The research was supported by NASA, the German Aerospace Center, and the Israel Space Agency.
Although the Artemis I mission did not encounter significant solar activity, researchers used the data collected as the Orion capsule passed through the inner Van Allen radiation belt to simulate the vest's effectiveness during extreme solar particle events. Historical solar outbursts, such as those in 1972 and 1989, had severe consequences, including causing electrical disruptions.
The findings indicate that the vest could reduce an astronaut's radiation dose by approximately 60% during a solar storm similar to the 1972 event and by nearly 40% during a storm comparable to the 1989 event. This level of protection could effectively negate the radiation exposure equivalent to 193 and 131 days of deep space travel, respectively.
With NASA planning lunar missions lasting weeks or months, the risk of encountering dangerous solar storms increases. Long-duration missions to Mars, such as those envisioned by SpaceX, would present even greater radiation challenges.
Researchers are currently working to reduce the vest's weight without compromising its protective capabilities. They are also exploring methods to create radiation shielding from materials already present on spacecraft, a strategy that could enhance crew safety and reduce mission costs.
Houri expressed confidence in the current dataset, stating that no further deep-space testing is anticipated in the near future. Zohar and her vest are now on display at the Kennedy Space Center in Florida.