did not see the initial event but when the ground area lit up in a big flash i looked up as i was already walking directly towards the fireball direction. the portion i saw was around mag -4 or - 5 but would have been much brighter to produce such a bright ground flash possibly -8 to -10. classic comet firework appearance 01.23 BST 00.23 UT near deneb in cygnus going towards the horizon.