A significant cosmic radiation anomaly has been identified in close proximity to the moon, potentially impacting the safety of astronaut journeys to the lunar surface.
Researchers have unveiled a newfound radiation “shadow” on the moon, where radiation levels decrease during specific hours, offering a potential safeguard for crews on upcoming space missions. These groundbreaking findings, derived from data collected by China’s Chang’e-4 lander, were recently published in Science Advances.
Central to this discovery is an enigmatic pattern of galactic cosmic radiation that diminishes during the moon’s local morning hours, shortly after sunrise. This period of reduced exposure could be pivotal for forthcoming manned missions, including NASA’s Artemis 2 mission, slated for a possible launch as early as April 1.
This revelation challenges prior assumptions about space radiation, which posited that cosmic rays disperse uniformly once they breach Earth’s protective magnetic field en route to the moon.
According to Robert Wimmer-Schweingruber, a professor at the Institute of Experimental and Applied Physics at Kiel University in Germany, the presence of this unexpected radiation “shadow” was a surprising but logical observation. The study, based on data from 31 lunar cycles spanning from January 2019 to January 2022, focused on periods of low solar activity to accurately gauge cosmic radiation levels. Instruments aboard Chang’e-4 tracked incoming protons across various energy spectrums.
The research revealed a 20% decline in lower-energy protons (ranging from 9.18 to 34.14 mega-electron-volts) during lunar mornings in the waxing gibbous phase. Computational models corroborated these findings, confirming the authenticity of this radiation reduction phenomenon.
The team hypothesizes that Earth’s magnetic field intercepts high-energy protons, creating a shielded area that influences radiation levels in space beyond expectations. This suggests that the Earth’s magnetosphere extends its protective influence further into space than previously believed.
Cosmic rays pose a significant radiation hazard for astronauts traveling beyond low Earth orbit, capable of penetrating spacecraft hulls and human tissue, leading to DNA damage and an increased cancer risk.
Prof. Wimmer-Schweingruber anticipates that future lunar landings will likely target polar regions exposed to constant sunlight. Venturing out onto the lunar surface in the morning hours could potentially reduce astronauts’ radiation exposure by approximately 20%.
“It is advisable for astronauts to explore the lunar surface during local morning hours, akin to human behavior on Earth,” added the professor.
