the edge of space
An introduction to our active
ionosphere
begin
Layers of the Atmosphere
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Troposphere
Stratosphere
Mesosphere
Ionosphere
(aka thermosphere)
Magnetosphere
0 – 18 km
5 – 50 km
50 – 90 km
90 – 600 km
weather
ozone layer
shooting stars
space shuttle, aurora
60,000 km
edge of space
Temperature change
The density of
the atmosphere
decreases with
increasing
altitude
Temperature
varies greatly
throughout the
atmosphere –
defining its
layers.
Chemicals in the Atmosphere
Nitrogen (N2) 78%
Oxygen (O2) 21%
Argon (Ar) 1%
Water Vapor (H2O) 0-7%
Ozone (O3) 0-0.01%
Carbon Dioxide (CO2)
0.01-0.1%
What is the Ionosphere?
• It is a conducting layer in the atmosphere that can reflect
radio signals (learn more).
• It protects us from dangerous radiation.
• It is the closest natural plasma (0.1% ionized plasma from
70 – 1500 km)
Why study the ionosphere?
• To increase the accuracy of the Global Positioning
System (GPS) learn more
• To increase the reliability of worldwide radio
communication with High Frequency radio waves. This
was studied extensively during World War II
• To increase the effectiveness of satellite communications
• To determine the connection, if any, between the
ionosphere and our weather.
• To understand better the interaction between the sun
and the Earth.
Solar Storms
From time to time, the sun emits huge amounts of plasma into the solar
system. Although the magnetosphere shields the Earth from most of the
radiation, some penetrates through to the ionosphere. Once there, it can
cause all sorts of trouble. Scientists need good space weather forecasts
to prepare for these disturbances. (learn more)
Anatomy of the ionosphere
• D layer (50 – 95 km)
absorbs some radio
waves
• E layer (90 – 140 km) first
part discovered
• F layer (160 – 400 km)
absorbs most of the
harmful UV radiation from
the sun. The ozone layer
absorbs the rest of it.
• Radio waves reflect off
both the E & F layers
Day & Night
The ionosphere changes
dramatically every night.
Without the influx of
solar power, the matter
loses some of its energy.
This decreases the
plasma density,
especially at lower
altitudes. AM radio
waves take advantage
of this “higher”
ionosphere and reflect to
farther distances. (learn
more)
The Magnetosphere
protects the ionosphere from the solar wind (the
charged particles emitted by the sun). The sun
sometimes emits very large amounts of matter all at
once in a coronal mass ejection (CME). This can lead
to solar storms which knock out communications
worldwide. (learn more)
Really cool movies!!!
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Our active sun
CME
Magnetosphere animation
magnetosphere data