Ionosphere

thumb|upright=2|Relationship of the atmosphere and ionosphere The ionosphere () is the ionized part of the upper atmosphere of Earth, from about to above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on Earth. Travel through this layer also affects GPS signals, deflecting their paths and delayi

thumb|300 px|Artist's impression of a magnetosphere

temporary disturbance of the Earth's magnetosphere caused by a disturbance in the interplanetary medium

University of Alaska Fairbanks program that investigates the ionosphere

peaks in the Earth's electromagnetic field spectrum, named for Winifred Otto Schumann

right|thumb|250px|Radio waves (black) Reflection (physics)|reflecting off the [[ionosphere (red) during skywave propagation. Line altitude in this image is significantly exaggerated and not to scale.]]

set of currents that flow along geomagnetic field lines connecting the magnetosphere to the ionosphere

layer of the Earth's ionosphere

Enhanced ionization of the ionosphere

right|thumb|EISCAT Kiruna Radar (diameter 32m)

type of radio propagation

radioastronomical observatory

250px|thumb|right|Typical ionogram indicating an [[F2 layer critical frequency (foF2) of approximately 5.45 MHz.]] thumb|right|An example of an ionosonde system displaying an ionogram

electromagnetic wave propagating through the atmosphere that may be detected by a sensitive audio amplifier as a gliding high-to-low-frequency sound; originates during lightning discharges and are usually in the frequency range of 300 to 30,000 hertz

The TIMED (Thermosphere • Ionosphere • Mesosphere • Energetics and Dynamics) mission is dedicated to study the influences that energetics and dynamics of the Sun and humans have on the least explored and understood region of Earth's atmosphere – the Mesosphere and Lower Thermosphere / Ionosphere (MLTI). The mission was launched from Vandenberg Air Force Base in California on 7 December 2001 aboard a Delta II rocket launch vehicle. The project is sponsored and managed by NASA, while the spacecraft was designed and assembled by the Applied Physics Laboratory at Johns Hopkins University. The miss

Type of radio propagation

layer in ionosphere

descriptive quantity of the Earth's ionosphere