With Artemis safely home, NASA eyes radiation for future flights

Now that the Artemis II spaceflight has successfully concluded with a stunning splashdown, NASA scientists will focus heavily on radiation exposure to astronauts in deep space where background radiation levels are 100 times Earth. Solar flares make exposure levels dramatically more perilous.

RELATED: Perfect Orion splashdown caps record Artemis II mission around the Moon

It is not an exaggeration to say that the future of crewed Artemis missions and future missions to Mars depend heavily on how much radiation was detected aboard the Orion spacecraft and in the bodies of the four astronauts.  Over a 10-day mission, radiation levels will not be as high as they would be over the seven months required to reach Mars. 

The four astronauts were deemed in excellent health when they splashed down, but full radiation evaluations will require weeks of study. Space medicine looks at five primary hazards astronauts face during spaceflight and NASA has developed an acronym called RIDGE, for Radiation, Isolation and Confinement, Distance from Earth, Gravity Fields and Environments. Over nine months in space, the human body experiences accelerated aging, because the heart and blood vessels do not have to pump against gravity and start to weaken. That phenomenon will be weighed against the radiation threat. 

The Artemis II measurements came down to a variety of sensors, as Fierce noted throughout the 10-day mission. Artemis I used  thousands of sensors to detect radiation to see what radiation exposure there was to the spacecraft, and Artemis II focused more centrally on how the astronauts were affected by it.

The measurements were the first modern, high-resolution measurements of the actual deep space radiation environment of both galactic cosmic rays and solar particles experienced by the astronauts and bio tissues in Orion. 

Key sensors

• Orion had six active Hybrid Electronic Radiation Assessors in the crew module.  ADVACAM, a company based in ,  provided critical chips used in HERA.  ADVACAM’s chips were timepix pixel chips. 
• Crew members wore personal dosimeters.
•  A  German Space Agency M-42 EXT sensor was included to distinguish radiation types including heavy ions. It had six times the resolution of the Artemis I version. 

All these sensors provided real-time monitoring for solar flares which would help the crew know when to shelter with stowed materials used as shielding to absorb radiation. Tests have already determined shielding can reduce a radiation dose by 50%.  Detailed post-flight data will map dose rates and the effectiveness of the capsule.

AVATAR organ chips

Each astronaut—Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen– wore USB-sized devices to detect the impact on bone-marrow tissue inside that was grown from each of their stem cells. 

As a control, identical devices were kept on Earth for direct comparison to those worn by the crew to detect the impact of deep space radiation and microgravity. Scientists will analyze cellular damage and blood cell impacts for each astronaut.

Data collection will last for a month following the splashdown, and the data will be shared on the NASA Life Sciences Data Archive. 

Peer reviewed biology and AVATAR results could take six months to 18 months to complete. At that point, NASA will being shaping any needed changes to vehicle designs and the timelines for lunar habitation and the first Mars missions. NASA deemed the radiation hardening of the capsule sufficient to allow the Artemis II flight to move ahead 

 A timeline for a crewed landing on the Moon is set for sometime in 2028, once a lunar lander is chosen.  Should all go well, plans to go to Mars are expected to include more sensors based on future technology insights. Even AI will be used to improve predictions for solar flares to give astronauts more time to shelter.