Navigating Deep Space Radiation

When the Artemis 2 crew ventures beyond the protective shield of Earth’s atmosphere and magnetic field, they will be exposed to space radiation. To ensure safety, the astronauts will remain vigilant by monitoring radiation detectors and listening for specific caution and warning alarms. Each crew member will be equipped with active dosimeters to measure real-time exposure to X-rays and gamma rays.

The Orion Spacecraft as a Shield

The Orion spacecraft is designed with significant shielding to protect its inhabitants. According to Stuart George, radiation instrumentation lead at NASA’s Space Radiation Analysis Group, the compact and dense nature of the vehicle provides effective protection. Data gathered from the uncrewed Artemis 1 mission confirmed that Orion performs well as a radiation shield.

Emergency Shelter Protocols

If the crew encounters a powerful solar particle event, they are prepared to take defensive measures. Astronauts will construct a makeshift shelter by moving contents from storage bays to a specific "hot spot" within the capsule. By placing these materials along the least shielded walls, the crew can create a lower-dose region to minimize their radiation exposure. In extreme scenarios, the crew can retreat to tighter, more shielded areas, such as the space near the toilet or specific storage bays.

Advanced Monitoring Technology

The Artemis 2 mission will utilize sophisticated tools to gauge radiation levels throughout the roughly 10-day trip. The crew will wear small Crew Active Dosimeter badges, while six Hybrid Electronic Radiation Assessors (HERA) are deployed throughout the crew module. Additionally, NASA has partnered with the German Space Agency (DLR) to include four updated M-42 EXT sensors, which offer six times the resolution of previous models to better distinguish between different energy types.

Defining Safety Thresholds

NASA has established predefined "go, no-go" dose rate thresholds for solar particle events. If these levels are exceeded, the crew will immediately initiate the shelter-building protocol. This strategy builds upon lessons learned from Artemis 1, which utilized instrumented "phantom" torsos to measure radiation effects on internal organs versus skin exposure.