The streaks that cut diagonally across them are " fireballs . "
斜穿过它们的条纹就是“火球”。
Firefighters spent four hours trying to seal the gas pipe , as orange fireballs spewed from a factory building roof .
消防员花了四个小时试图封堵输气管道，橙色的火球从一幢工厂建筑的屋顶中喷出。
It seems at least three individual fireballs were seen on the night of 16 may 2006 .
据说2006年5月16日晚人们看到了至少三个不同的火球。
For another , the artificial fireballs seem to be glowing because of the excitation of theatoms within the vaporised material rather than because of oxidation .
另一方面：人工的火球看起来炽热的是由于在蒸汽态的原子的激发而导致，而不是由于氧化。
His idea is that one of the fireballs may have momentarily triggered an electrical connection between the upper atmosphere and the ground , providing energy for the ball lightning to appear above the hills .
