Figure 11-8: R I V U X G
The Caloris Basin About 4 billion years ago an impact on Mercury created an immense basin, shown in orange in this enhanced-color MESSENGER image. The crater is about 1500 km (960 mi) in diameter. The impact fractured the surface extensively, forming several concentric chains of mountains. The mountains in the outermost ring are up to 2 km (6500 ft) high. Craters inside the basin (shown in blue) were formed later by smaller impacts.
The Caloris Basin About 4 billion years ago an impact on Mercury created an immense basin, shown in orange in this enhanced-color MESSENGER image. The crater is about 1500 km (960 mi) in diameter. The impact fractured the surface extensively, forming several concentric chains of mountains. The mountains in the outermost ring are up to 2 km (6500 ft) high. Craters inside the basin (shown in blue) were formed later by smaller impacts.
(NASA/Johns Hopkins U. Applied Physics Laboratory/Arizona State U./Carnegie Institution of Washington)