Natural shielding

Earth could shield Moon colonists from radiation | COSMOS magazine

For about seven days a month, the Moon’s orbit carries it inside the protective cocoon of Earth’s magnetic field, where it is partially shielded from the Solar System’s turbulent space weather. Could future colonists use this to their advantage?

A new study suggests that space agencies could use this natural radiation screen when constructing lunar bases or planning the moonwalks of future astronauts.

“The terrestrial magnetic field provides a significant amount of shielding for energetic particles incident on the Moon,” said Robert Winglee, a physicist at the University of Washington in Seattle, USA. “An astronaut, especially if he was far off from base, would be very well protected.”

That's encouraging.