Instead of thanking your lucky stars you were able to fall asleep so quickly, you might want to thank the moon. Apparently, the alignment of the moon with the sun does more than change the appearance of it in the sky. It can also affect your sleep cycle. One study showed that children actually slept for longer during phases of the full moon. Conversely, another study suggested that the full moon causes a decrease in sleep efficiency and prevents people from sleeping as deeply. How exactly the moon affects your slumber is still pretty hazy — but it certainly has an impact.