when i was 13 myself and my mother were looking at a car accident appox 200 yards from our address in seacroft leeds uk,we turned to come away and there was a massive purple ball of light that engulfed the entire sky moving from n/e to n/w we ducked as it came over our heads but when we looked up in the direction where it was heading it had gone, the ole thing lasted no more than ten seconds if that but was very scary please let me know if anybody knows what it might have been.