1) Atmospheric science
Found on
https://www.crosswordclues.com/clue/riometer
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, th.....
Found on
http://en.wikipedia.org/wiki/Riometer
instrument for measuring absorbed cosmic radio waves
Found on
http://phrontistery.info/r.html
a calibrated radio receiver tuned to a fixed frequency between 10 and 100 MHz, used to record the flux of cosmic noise; this flux can be used to determine time variations of ionospheric absorption NOTE - The term 'riometer' is a contraction of 'Relative Ionospheric Opacity Meter'.
Found on
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=705-07-80
No exact match found.
