A wearable radiation shield called AstroRad cut simulated solar storm doses by roughly 60 percent during the uncrewed Artemis I flight around the Moon, according to the first in-flight evaluation published August 14 in Science Advances. Jordan Houri of MIT and colleagues from several institutions flew two female phantom torsos aboard the Orion spacecraft in late 2022.
One wore the AstroRad vest, designed by the Israeli firm StemRad and NASA to protect bone marrow and lungs. The other went bare. Both carried passive and active dosimeters. During the spacecraft's transit through the inner Van Allen radiation belt, the team measured actual dose rates, then extrapolated those numbers to model two historically severe solar particle events: the August 1972 storm and the October 1989 event. For the 1972 scenario, the vest would have reduced effective radiation dose by about 60 percent, sparing astronauts the equivalent of up to 193 days of accumulated deep-space exposure. For the 1989 event, the reduction was closer to 40 percent, or about 131 days worth.
The numbers matter because NASA is planning crewed missions back to the lunar surface within the next few years, and a major solar particle event during transit could be lethal without protection. The Artemis II crew already completed their own lunar flyby earlier this year, proving the Orion spacecraft can keep humans alive in deep space.
The question now is whether wearable shielding alone is enough, or whether crews will also need dedicated storm shelters built into the vehicle.