Artemis I Radiation Measurements Validate Orion’s Safety for Astronauts

Oct. 10 () –

NASA researcherstogether with several collaborators, have led, during the unmanned Artemis I mission, payloads aboard Orion to measure the possible radiation exposure of astronautsas reported by the US space agency.

The measurements show that while radiation exposure may vary depending on location within Orion, the spacecraft can protect its crew from potentially dangerous radiation levels during lunar missions.

The NASA Orion space probe is designed to keep astronauts safe in deep space, protecting them from the unforgiving environment far from Earth.

During its 25.5-day mission around the Moon and back, Orion performed radiation measurements using 5,600 passive sensors and 34 active radiation detectorswhich provided important data on exposure within Earth’s Van Allen radiation belt.

These detailed findings were published in a recent scientific paper thanks to a joint effort by NASA’s Space Radiation Analysis Group, DLR (German Space Center) and ESA (European Space Agency).

Space radiation could pose significant risks to long-duration human spaceflight, and the findings from the Artemis I mission represent a crucial step toward future human exploration beyond low-Earth orbit, toward the Moon and, eventually, towards Mars.

NASA’s HERA (Hybrid Electronic Radiation Assessor) and Crew Active Dosimeter, which were previously tested on the International Space Station, and ESA’s Active Dosimeter, were among the instruments used to measure radiation inside Orion.

HERA’s radiation sensor can warn crew members to take shelter in the event of a radiation event, such as a solar flare. The Active Crew Dosimeter can collect real-time radiation dose data for astronauts and transmit it to Earth for monitoring. Radiation measurements were carried out in several areas of the spacecraft, each with different levels of protection.

Additionally, the Matroshka AstroRad Radiation Experiment, a collaboration between NASA and DLR, involved radiation sensors placed on and inside two life-size mannequin torsos to simulate the impact of radiation on human tissue. These mannequins allowed radiation doses to be measured in various parts of the body, providing valuable information about how radiation can affect astronauts traveling into deep space.

Researchers found that Orion’s design can protect its crew from potentially dangerous levels of radiation during lunar missions. Although the spacecraft’s radiation shielding is effective, The exposure range can vary greatly depending on the orientation of the spacecraft in specific environments.

When Orion altered its orientation during an interim cryogenic propulsion stage engine burnout, radiation levels were reduced by almost half due to the highly directional nature of radiation in the Van Allen belt.

“These radiation measurements demonstrate that we have an effective strategy to manage radiation risks on the Orion spacecraft. However, key challenges remain, especially for long-duration spaceflight and protecting astronauts during spacewalks,” said Stuart George, lead author of the NASA paper.

NASA is conducting long-term research and efforts to mitigate the risks of space radiation, as radiation measurements on future missions will largely depend on the shielding, trajectory and solar activity of the spaceship.

The same radiation measurement equipment used on Artemis I will support the first crewed Artemis mission around the Moon, Artemis II, to better understand the radiation exposure observed within Orion and ensure the safety of astronauts on the Moon and beyond.