Via: Spaceweather. http://spaceweather.com/
Yesterday, Feb. 2nd, the solar activity forecast called for “quiet.” In fact, says amateur radio astronomer Thomas Ashcraft, “it was really loud. There were several strong solar radio emissions including one super-strong Type III burst at 1954 UT. I captured it at 28 MHz and 21.1 MHz as it totally drowned out a short wave voice transmission.”
The source of the burst was sunspot AR1667, which unleashed a C2.9-class solar flare just before the roar emerged from the loudspeaker of Ashcraft’s radio telescope. Type III solar radio bursts are produced by electrons accelerated to high energies (1 to 100 keV) by solar flares. As the electrons stream outward from the sun, they excite plasma oscillations and radio waves in the sun’s atmosphere. When these radio waves head in the direction of Earth, they make themselves heard in the loudspeakers of shortwave radios around the dayside of the planet. Go to http://spaceweather.com/ for more info.