The troposphere can extend from the planet's surface to a heightbetween 3.5 to 12.5 miles (6 and 20 km). This lowest layer contains more than 80 percent of the massof the atmosphere and almost all ...

High in the upper atmosphere, from the edge of space to well within it, there is the ionosphere. Atoms and molecules there are missing electrons, so they are electrically charged. They are ...