John Oakley, age 12, of Bellevue, Wash.,

How high is the ionosphere?

The ionosphere is a slice of the earth’s atmosphere about 600 miles thick. It begins about between 50 and 60 miles above our heads and reaches up about 650 miles. Up there, the air is very, very thin. Many of the tiny air particles are ionized, or charged with electricity which explains why this layer of the earthts atmosphere is called the ionosphere.

Radio waves fan out in all directions and those that reach the ionosphere are bounced back at different angles to the earth. The layer of charged particles acts somewhat like a sounding board for our radio also signals. And after a rash of sunspots on the sun, it/may treat us to a glimmering display of Northern Lights.