FORECAST SOL: Moderate yellow MAG: Normal green ION: Normal green
HomeSolarLearmonth ObservatoryRadio Flux Tuesday, Jul 16 2024 15:45 UT
Learmonth Observatory

Radio Flux

The Sun is what we call a broadband emitter: it gives off radiation over a very wide frequency range. The Learmonth solar radio telescopes monitor both the quiet and active Sun, at 245, 410, 610, 1415, 2695, 4995, 8800, and 15400 Mhz.

The background solar radio emission (the quiet Sun) can be used as a source to calibrate other electronic equipment. ASWFC makes available the Learmonth Quiet Solar Flux or IFLUX for this purpose. Solar radio bursts (the active Sun) can exceed the background solar radio emissions by several orders of magnitude. Solar radio emissions can cause interference to man made electromagnetic systems (eg, radio, radar, and GPS). It is also useful to know that the source of the interference comes from the Sun, rather than another man made source, or an equipment fault.

These solar radio emissions also indicate the strength of the solar activity, and help predict the arrival of high energy solar protons at the Earth, which can degrade solar panels of spacecraft, and cause transpolar HF circuits to become disrupted (PCA event). A strong burst on the 1415MHz frequency may indicate that some GPS satellite signals could be lost, if the GPS satellites are near the position of the Sun in the sky. Plots of solar radio emission strength at 8 frequencies from 245 to 15400 Mhz are provided from the links below.

Note that these solar radio telescopes can sometimes themselves be affected by man made radio frequency interference, resulting in a large spike appearing in the plots.

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