It's well known that many animals, including migratory birds, butterflies, and even fish, use the sun for navigational purposes. Nocturnal animals are dealt a more difficult hand, however, as the moon's path is far more variable. But a new study, published in Current Biology, has shown that nocturnal bull ants (Myrmecia midas) not only use the moon as a compass, but are also capable of accounting for speed variations in its movement.