ionosphere
[ ahy-on-uh-sfeer ]
/ aɪˈɒn əˌsfɪər /
noun
the region of the earth's atmosphere between the stratosphere and the exosphere, consisting of several ionized layers and extending from about 50 to 250 miles (80 to 400 km) above the surface of the earth.
OTHER WORDS FROM ionosphere
i·on·o·spher·ic [ahy-on-uh-sfer-ik] /aɪˌɒn əˈsfɛr ɪk/, adjectiveWords nearby ionosphere
ionone,
ionopause,
ionophore,
ionophoresis,
ionosonde,
ionosphere,
ionospheric wave,
ionotropic receptor,
ionotropy,
iontophoresis,
ioof
Example sentences from the Web for ionosphere
British Dictionary definitions for ionosphere
ionosphere
/ (aɪˈɒnəˌsfɪə) /
noun
Derived forms of ionosphere
ionospheric (aɪˌɒnəˈsfɛrɪk), adjectiveScientific definitions for ionosphere
ionosphere
[ ī-ŏn′ə-sfîr′ ]
A region of the Earth's upper atmosphere, extending from a height of 70 km (43 mi) to 400 km (248 mi) and containing atoms that have been ionized by radiation from the Sun. The ionosphere lies mostly in the lower thermosphere and is subdivided into three regions, the D region (70 km to 90 km; 43 to 56 mi), the E region (90 km to 150 km; 56 to 93 mi), and the F region (150 km to 400 km; 93 to 248 mi). The concentration of ionized atoms is lowest in the D region, intermediate in the E region, and highest in the F region. The ionosphere is useful for radio transmission because radio waves, which normally propagate in straight lines, are reflected off the ionized gas particles, thereby being transmitted long distances across the Earth's curved surface. See more at D region E region F region.
Cultural definitions for ionosphere
ionosphere
[ (eye-on-uh-sfeer) ]
A region of the atmosphere that begins at an altitude of about thirty miles.
notes for ionosphere
In this region, free particles carrying an electrical
charge,
atoms ionized (
see
ionization) by
radiation from the
sun, reflect
radio waves. “Bouncing” radio waves off the ionosphere makes communication possible over long distances of the surface of the
Earth.