Mercury Is Slowly Shrinking as Its Massive Iron Core Cools
As Mercury's gigantic iron core cools and contracts, the planet's outer crust buckles into towering cliffs, steadily shrinking its radius.
🪐 Cosmic Discovery
NASA Science
According to MESSENGER data, by roughly how many kilometers has Mercury's radius shrunk since its formation?
As the core cools and loses volume, the rigid crust wrinkles and thrusts upward like the skin of a drying apple.
🪐 Space
Cosmic Discovery
Why / How?
Scientific Mechanism
NASA's MESSENGER spacecraft mapped towering fault scarps stretching hundreds of kilometers across Mercury. These lobate scarps form as the planet's massive iron core cools and contracts, forcing the brittle outer crust to thrust upward and overlap.
Why It Matters
As the core cools and loses volume, the rigid crust wrinkles and thrusts upward like the skin of a drying apple.
