Labels:text | screenshot OCR: STRUCTURE Mantle ATMOSPHERE Mercury's surface gravity is too weak to hold on to gas particles near the surface. As a result, Mercury's atmosphere is virtually nonexistent, being about 1,000 billion times less dense than the Earth's atmosphere. | Core Crust LAYER THICKNESS COMPOSITION Crust Silicate rock Mantle 600 km (370 miles) Silicate rock Core (radius) 1,800 km (1,100 miles) Iron and nickel
