Radio Signatures of Sunspot NOAA 12192


In this paper, we present an overview of radio signatures of sunspot NOAA 12192 measured with various instruments with frequencies of 37 GHz, 11.2 GHz and 200 - 400 MHz at Aalto University Metsahovi Radio Observatory (MRO). The data were observed during October 20 - 29, 2014. In total, 12 solar radio bursts at 11.2 GHz and 8 at 200 - 400 MHz, with varying intensities and properties, were observed. Radio brightening was captured in several solar radio maps. NOAA 12192 is the largest observed sunspot during solar cycle 24. We show that this exceptional radio brightening belongs to the strongest category including less than 5% of radio brightenings ever measured at MRO.

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Uunila, M. and Kallunki, J. (2014) Radio Signatures of Sunspot NOAA 12192. International Journal of Astronomy and Astrophysics, 4, 649-655. doi: 10.4236/ijaa.2014.44059.

Conflicts of Interest

The authors declare no conflicts of interest.


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