Its surface, marked by craters and barren plains, gives little hint of the mysteries beneath. But recent discoveries have revealed something extraordinary: a massive heat-emitting feature buried deep within the lunar crust.

This enigmatic finding, hidden beneath the Moon's far side, defies expectations. It involves a rare material, typically associated with Earth, and raises fascinating questions about the Moon's past. What could cause such heat on a body long thought to be geologically dormant? And what does this mean for our understanding of the Moon—and perhaps even other planets?

In a groundbreaking revelation, scientists have identified a substantial heat-emitting granite mass beneath the Moon's surface, specifically near the Compton and Belkovich craters on its far side. This discovery was made possible through data collected by both Chinese and American lunar orbiters, which utilized microwave frequency observations to detect subsurface temperatures. Dr. Matt Siegler of the Planetary Science Institute explained, "We used an instrument that observes microwave wavelengths, longer than infrared, sent to the Moon on both the Chinese Chang'E 1 and 2 orbiters. We found that one of these suspected volcanoes, known as Compton-Belkovich, was absolutely glowing at microwave wavelengths."

The data revealed a silicon-rich surface feature approximately 20 kilometers wide, believed to be the caldera of an ancient volcano. This area exhibited temperatures about 10°C warmer than its surroundings. Notably, this heat is not due to current volcanic activity, as the last eruption occurred around 3.5 billion years ago. Instead, the heat emanates from radioactive elements trapped within the granite mass. Dr. Siegler noted, "We interpret this heat flux as resulting from a radiogenic-rich granite body below the caldera."

This finding is significant because granite formation typically requires water and plate tectonics—conditions absent on the Moon. The presence of such a large granite deposit suggests that the Moon's geological history may be more complex than previously understood. Dr. Siegler remarked, "If you don't have water, it takes extreme situations to make granite. So, here's this system with no water, and no plate tectonics—but you have granite."