On the full moon of the twelfth Thai lunar month, millions of banana-leaf boats (krathong) carrying candles, incense, and flowers are floated on rivers, canals, and ponds across Thailand. The offering honors the water spirits and the Naga, asks forgiveness for polluting waterways, and releases bad luck. In Chiang Mai, thousands of sky lanterns (khom loi) are released simultaneously, filling the night sky with fire.