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- Riometer abstract "A riometer (relative ionospheric opacity meter) (30 MHz) is an instrument used to quantify the amount of electromagnetic wave ionospheric absorption in the atmosphere. As the name implies, a riometer measures the ``opacity" of the ionosphere to radio noise emanating from distant stars and galaxies. In the absence of any ionospheric absorption, this radio noise, averaged over a sufficiently long period of time, forms a quiet-day curve. Increased ionization in the ionosphere will cause absorption of radio signals (both terrestrial and extraterrestrial), and a departure from the quiet-day curve. The difference between the quiet-day curve and the riometer signal is an indicator of the amount of absorption, and is measured in decibels. Riometers are generally passive radio antenna operating in the VHF radio frequency range (~30 MHz).The Riometer was developed in the mid 1950s by scientists at the University of Alaska who were researching the radio propagation effects of aurora. At times aurora resulted in complete failure of long distance radio communication to planes in the Arctic - a matter of considerable concern to the US Air Force at a time of tension with the Soviet Union.".
- Riometer wikiPageExternalLink Rio.html.
- Riometer wikiPageID "18350922".
- Riometer wikiPageRevisionID "592941420".
- Riometer hasPhotoCollection Riometer.
- Riometer subject Category:Atmospheric_sciences.
- Riometer comment "A riometer (relative ionospheric opacity meter) (30 MHz) is an instrument used to quantify the amount of electromagnetic wave ionospheric absorption in the atmosphere. As the name implies, a riometer measures the ``opacity" of the ionosphere to radio noise emanating from distant stars and galaxies. In the absence of any ionospheric absorption, this radio noise, averaged over a sufficiently long period of time, forms a quiet-day curve.".
- Riometer label "Riometer".
- Riometer label "Riometer".
- Riometer sameAs Riometer.
- Riometer sameAs m.04f49_4.
- Riometer sameAs Q119791.
- Riometer sameAs Q119791.
- Riometer wasDerivedFrom Riometer?oldid=592941420.
- Riometer isPrimaryTopicOf Riometer.