A Blanket With No Edge
Earth's atmosphere is a layer of gas held by gravity, but it has no sharp border with space. The Kármán line at 100 km is a practical marker, not a physical wall.Earth's Atmosphere and the Edge of Space
Most Of It Hugs The Ground
The atmosphere sounds vast, but three quarters of its mass sits within about 11 km of the surface. Half of all atmospheric mass is packed into the lower 5.6 km.Earth's Atmosphere and the Edge of Space
