Ancient Volcanoes on the Moon’s Far Side? Chang’e-6 Changes Everything We Knew

The Moon’s enigmatic far side has long been a mystery. Now, China’s Chang’e-6 mission has made a groundbreaking discovery, retrieving 2.83-billion-year-old basalt. This find redefines our understanding of lunar volcanic activity and the Moon’s geological evolution.

The Moon’s Far Side Is More Explosive Than We Imagined

Chang’e-6 collected nearly 2 kilograms of lunar soil from the South Pole-Aitken Basin, the largest and oldest known lunar impact site. This region, subjected to billions of years of asteroid impacts, holds clues to the Moon’s oldest geological history.

The samples from the Moon’s far side were collected using advanced drilling and scooping techniques, reaching depths of up to 6.5 feet. This allowed scientists to retrieve material from both the surface and subsurface, providing a detailed cross-section of the lunar crust.

Basalt is a volcanic rock formed from cooled lava. Rich in iron and magnesium, it is common on Earth and other rocky bodies in the solar system. The basalt revealed two distinct volcanic episodes, with the younger sample dating back 2.83 billion years.

Researchers observed that the retrieved basalt samples were lighter in color and less dense than near-side samples, suggesting a looser, more porous structure.

This discovery marks the oldest known far-side volcanic activity, challenging prior assumptions about the Moon’s evolution. Analysis showed the volcanic source lacked KREEP (potassium, rare earth elements, phosphorus), contrasting with near-side samples.

These insights refine lunar impact chronologies and suggest the Moon’s crust and mantle were shaped differently across hemispheres. The far side’s thicker crust may explain its reduced volcanic activity.

These findings were published in Science on 15 November 2024.