Despite its immense energy output, our Sun is fairly peaceful compared to most stars. But once in a while it springs a surprise. On Tuesday May 5, 2015, for example, the Sun suddenly erupted with its most powerful flare of the year. As the unexpected solar flare got underway, Slooh host Eric Edelman and Slooh astronomers Will Gater and Bob Berman jumped into action to cover the event along with a live solar telescope feed from a Slooh partner in Thunder Bay, Canada. You can see a video recording of the show and images at this link.
A solar flare is a sudden release of energy stored in twisted magnetic fields, usually near sunspots. The solar flare on May 5 was an X-class event, the most powerful class of solar flare. Flares produce a burst of charged particles and radiation across the electromagnetic spectrum which is ejected into space and often causes auroral activity in the Earth’s atmosphere a day or two later. Since they arrive at the speed of light, X-rays and gamma rays ejected from a solar flare can arrive sooner, just eight minutes after the flare. The X-rays released in the May 5th event caused extensive radio blackouts in western North America the same day.
Until the May 5th flare, the Sun had been quiet for some time. Slooh astronomer Bob Berman said of this event, “Just when we thought that the maximum peak of solar cycle number 24 was behind us, the Sun is coming up with violent surprises. It was fun to watch and share with Slooh’s members and the public, using special narrow-bandpass solar filters.”