Rocks From the Moon’s Hidden Side Are Rewriting the Story of Its Violent Youth

The far side of the Moon isn't dark—it receives just as much sunlight over time as the side facing Earth. Yet humanity had never seen it until the Soviet Luna 3 probe photographed it in October 1959, less than 56 years after the Wright brothers' first powered flight.

The phrase “dark side of the Moon” has survived because it compresses two kinds of invisibility into one. The Moon has a day side and a night side, determined by sunlight. It also has a near side and a far side, determined by the view from Earth. Those divisions are not the same. Sunlight moves across both lunar hemispheres. The far side was hidden for most of human history not because the Sun never reached it, but because the Moon keeps nearly …

Rocks From the Moon’s Hidden Side Are Rewriting the Story of Its Violent Youth

For most of the history of lunar science, humanity’s understanding of the moon’s ancient bombardment has come almost entirely from one hemisphere. The near side — the face that has stared at Earth for billions of years — is where the Apollo missions landed and where nearly every lunar sample analyzed in a laboratory originated. The far side, permanently turned away from us, remained largely a blank slate. New research analyzing rock fragments re…