Overview

• Microwave data has revealed a large granite formation beneath the Moon's surface, indicating ancient volcanic activity.
• The granite formation is much larger than expected, stretching 50 kilometers across.
• The presence of granite raises questions about the Moon's past geological conditions.
• The heat emanating from the granite comes from concentrations of radioactive elements within the rock.
• The discovery shows that the Moon may have once had active volcanism and plate tectonics.