There weren’t any humans strapped into the bucket seats of the Orion spacecraft for the Artemis I mission. But there were two anthropomorphic mannequins made to mimic human bone and soft tissue, but also equipped with hundreds of radiation sensors spread throughout their body as part of the Matroshka AstroRad Radiation Experiment. A recent paper led by Paweł Bilski of the Institute for Nuclear Physics of the Polish Academy of Sciences, and published in the journal Radiation Measurements, reports on the results of that experiment, including the operation of a new type of long-term passive radiation monitor made of lithium.

When dealing with radiation in deep space, scientists need to understand both its quantity and its physical quality.…