As space missions go farther and last longer, astronauts will be exposed to space radiation for extended periods. Research by NASA and ESA with the collaboration of scientists from research centers and universities around the world attempts to understand the radiation environment and the effect that radiation has on humans, with the goal of mitigating potential health risks.

The research concludes that future missions to the Moon are unlikely to expose astronauts to radiation greater than the limits set by NASA.

NASA dolls in space for research

The three-week Artemis I mission, which traveled uncrewed in 2022 to the Moon, orbited the Moon, and then returned to Earth, incorporated many sensors to measure radiation: at various locations inside the Orion spacecraft and on the two dummies which carries, Zohar and Helga. Helga flew without a lifejacket, while Zohar wore a lifejacket.

The sensors collected radiation data continuously during the journey between Earth and the Moon.

According to the first research results, published in the journal Nature, radiation exposure varied significantly by sensor location, with the most shielded areas providing four times more protection than the least shielded.

Radiation exposure from large solar particle events in the most heavily shielded region of the capsule remained below 150 millisievertswhich is considered one safe level to avoid acute radiation sickness.

This data validates the spacecraft’s armor design.

Also, the orientation of the spacecraft affected the radiation exposure. A 90-degree turn during Orion’s flyby in the inner Van Allen belt reduced radiation exposure by 50%, and this provides researchers with valuable information for future mission plans.