Although the Perseids tend to put out the greatest number of meteors during the wee morning hours, the moonlit glare will wash out many if not most Perseid meteors in 2009.
The last time a special Perseids shower like this one occurred was in 2009.
上一次这样壮观的英仙座流星雨出现在2009年。
Like other meteor showers, such as the Perseids and the Orionids, the Leonids happen when Earth plows through a trail of debris left in the wake of a comet orbiting the sun.