In the Hindu/Buddhist cosmos, eclipses are conceived of and anticipated in terms of the points of intersection of the paths of the Sun and the Moon as they move across the sky.  Rahu is the name for the north lunar node which, in mythological representation, is the Asura (Demon) Rahu who  regularly swallows and ejects the sun, causing its cyclic obscuration. In Thai custom, Phra Rahu, who is considered to be the essence of darkness and the harbinger of ill fortune, is ritually placated with various black offerings that are believed to mitigate his maleficence. People make offerings  of black grapes, black liqueur, black coffee beans, black jelly, black beans, black sticky rice, black Thai cake and black fermented eggs. In the course of my performance, at the Huai Khwang Shrine, I lit a black candle for him and then made a special offering Black herbal jelly in the form of  the Suriyan (the Sun) or as he is know in Thailand, Phra Athit.

https://www.thaiworldview.com/bouddha/animism3.htm