Tomorrow is Hachigatsu Bon, or the August celebration of Obon. What is Obon? It is a Japanese Buddhist festival held in honor of the dead, similar to the Mexican Day of the Dead. Offerings are made to one's ancestors to make their time in the afterlife more comfortable, and paper lanterns called toro nagashi are lit and floated on the water to signal the spirits' return to... well, wherever it is they return to. To be honest I am not very well informed on Japanese theological matters and I've not have much luck finding good sources of information.