Note, moths do not actually try to fly into lights...
Instead the moth thinks it is the moon, and tries to navigate by it. This turns their straight line into something decidedly not-straight, resulting in the characteristing flight pattern. :-)
Cheers,
Ben
"... I couldn't see how anyone could be educated by this self-propagating system in which people pass exams, teach others to pass exams, but nobody knows anything."
--Richard Feynman