The Sun, photographed by NASA's Skylab 4. This photograph shows one of the most spectacular solar flares ever recorded; the base of the flare is more than 591,000 km across. From www.britannica.com
"As long ago as the Ice Age, when our species was in its childhood, man found in fire a powerful ally in his fight against cold and darkness, and it helped him make a considerable step towards his domination of the world around him. The real nature of fire, which, according to antique lore, Prometheus stole from Heaven, the home of lightning, remained unexplained far into later ages. In fact fire is in all probability the first chemical reaction which mankind took into his service."
From the presentation speech by Professor Gerard de Geer, President of the Royal Swedish Academy of Sciences, to Professor Geheimrat Nernst winner of the Nobel Prize for Chemistry, 1920. http://www.nobel.se/chemistry/laureates/1920/press.html