The image below shows x-rays streaming off the Sun as seen by NASAs NuSTAR telescope array system. Se http://phys.org/print346063299.html …
scientists are trying to understand a new kind of explosion seen on the Sun, described as nano flares – much less energetic than ordinary flares. The Sun can go fro days, weeks, even months without producing an ordinary solar flare. Nano flares are crackling all the time – almost non-stop. It is hoped that nano flares will eventually explain why the Sun's corona is so hot. It is described as one the most vexing problems in astrophysics.
Nano flares are active throughout the solar cycles – which explains why the Sun stays so hot even during periods of low activity (with few sun spots).
Meanwhile, Canadian and Japanese astronomers are working together on x-ray observations, the ASTRO-H. The telescope is designed to explore x-rays and other features of the universe in great detail – homing in on black holes. Go to http://phys.org/print346075385.html … scientists from the University of Waterloo in Ottawa are involved.