Thor | Britannica"Thor, also spelled Thorr, Thunor, Thonar, Donar, Donner, Thur, Thunar, or Thunaer, in Norse mythology was the god of thunder and the sky. Thor was the eldest son of the chief deity, Odin, and Jorth. He was second only to Odin in importance and was probably the most popular god of the Norse pantheon. Thursday, the fifth day of the week, was named for Thor; the name is believed to be derived from Jupiter Tanarus, the Thundering Jupiter, a Celtic deity ..."