active Sun (4 facts) - The Sun during its 11-year cycle of activity when spots, flares, prominences, and variations in radiofrequency radiation are at a maximum.
Forbush decrease (6 facts) - A decrease in cosmic-ray intensity during active Sun.
solar burst (3 facts) - Suddenly enhanced nonthermal radio emission from the high solar corona immediately following a solar flare, probably due to energetic electrons trapped in the coronal magnetic field. Bursts are divided into several types, depending on their time frequency characteristics (type III is the most common). They are classified on a scale of importance ranging from -1 (least important) to +3. Bursts are generally attributed to a sudden acceleration of some 1035-36 electrons to energies greater than 100 keV in less than 1 second.
solar cycle (4 facts) - The 11-year period between maxima (or minima) of solar activity. Every 11 years the magnetic field of the Sun reverses polarity; hence the more basic period may be 22 years.
solar flare (11 facts) - Sudden and short-lived brightening of a region of the solar chromosphere.