Of all the jewels that get washed down to their underwater palaces, dragons value pearls beyond all else and for this reason they are a great peril to pearl-divers, whom they see as thieves. In China it is believed that pearls are droplets that fall like rain from the moon into the sea, where they are often swallowed by oysters. So it follows that the pearl which dragons long for most of all is the moon itself. Many have been known to go mad with infatuation and try to steal it from the sky, resulting in a lunar eclipse.
This love has been fixed in the stars with the constellation of the dragon forever chasing the moon across the sky. It is also celebrated in the timing of the Chinese New Year, when the moon rises just beyond reach of the starry dragon, a sign of hope that the mistress of tides and fruitfulness will always escape such rash and consuming lust.
Some dragons are also said to have tried to swallow the sun, but the Chinese traditionally believed it was always doomed to be burned to a cinder. With the moon there was some doubt and real fear that any lunar eclipse might lead to it disappearing forever, but not with the sun. For this reason many Chinese magistrates used to have a dragon trying to swallow the sun embroidered on their silken robes and wall hangings. It was to declare to the world that it was as impossible for them to be bribed as it was for a dragon to swallow the sun. Whether this was actually true was of course as subject to human vagary as in any other part of the world.