InFlaMo – an European SID Monitoring Network Celebrates its First Solar Cycle

The influence of solar X-ray radiation on terrestrial radio communication was found in the early 20ies century. But it was not understood immediately. Radio communication was a challenging topic back then, and became quickly a topic taught in science classes at school. Half a century later – with the start of the space age - it became evident, that the study of Earth's upper atmosphere was solving this question. Solar and other cosmic radiation is responsible for the condition of the ionosphere and the cause of black-outs in long range radio communication. Today, most of the ionospheric very long frequency (VLF) radio propagation phenomena are known and presumably almost completely understood, though it stays a challenging topic listening to the ionospheric disturbances caused by our Sun. The recent development of low-cost software defined radio wave receivers (SDRs) are an ongoing process and opens many new opportunities for applications in people's daily lives and in education. Furthermore, monitoring of Earth's lower ionosphere by utilizing VLF monitors, which are based on SDR technology, it offers new indirect insights into what happens on the Sun. Therefore, one aim of this presentation is to reach out to an educator community as well as citizen scientists to make the InFlaMo (Indirect solar Flare Monitoring) project (http://www.inflamo.org) better known. For almost the entire solar cycle 24 VLF data (20 to 30 kHz) was collected and preprocessed. The scientific analysis of the VLF data is an ongoing activity. For scientific and educational use InFlaMo project data is shared with researchers, educators and citizen scientists. The other aim is to enlarge the network of ground based multichannel SDR-receivers from Europe to overseas. The European network stations have been or are presently in Germany, Finland, Russian Federation and Czech Republic. With this rather inexpensive method monitoring the state of the ionosphere and recording the appearance of solar X-ray flares can be made available for class-room usage.