Earth's Atmosphere extends, gradually thinning, to 1,000
1/2 is below 3 1/2 miles.
Because of Turbulence, composition
to 45 miles is 78% Nitrogen, 21% Oxygen, .03% Carbon Dioxide, and .04%
Argon, Neon, Radon, Helium, Krypton, Xenon, Methane, Nitrous Oxide, &
Also, up to 4% Water-Vapor, Dust, Salt, Carbon Monoxide,
Micro- Organisms, & Industrial Chemicals.
Above 500 miles are Helium & Hydrogen
TROPOSPHERE - Up to 5 miles
above Poles & 11 miles above
Clouds, Weather, Heated by Earth Surface, Vertical Air Currents &
TROPOPAUSE - Boundary between Troposphere &
STRATOSPHERE - Up to 30 miles.
Near weatherless, little Vertical Air motion, Temperature drop slows -
increases near top
MESOSPHERE - 30 - 50 miles
Temp. drop from 30 to -100 F at top
THERMOSPHERE - 50 - 500 miles
Ionized Particle Layers - Reflect Long Radio Waves, E Layer 50-80
mi. up & F Layer 150-200 mi., Temp. varies (at 300 mi.) from 2,500+
F in Day to 300 at Nite, Aurora occur
EXOSPHERE - 500 - 1,000 miles
Ionized Atomic Hydrogen & Helium, 4,500 degrees F in Day, -450 F at Nite