sentences:  On September 14, 2001, scientists at the Arecibo Observatory photographed a gigantic jet—double the height of those previously observed—reaching around into the atmosphere.The jet was located above a thunderstorm over an ocean, and lasted under a second.The jet was initially observed to be traveling up at around at a speed similar to typical lightning, increased to , but then split in two and sped upward with speeds of at least to the ionosphere where it then spread out in a bright burst of light.