An hour is just an another name for a deciturn, or a deciday. Tau is not a good unit for angles in general, unless you have circles, or you need lengths of cir

An hour is just an another name for a deciturn, or a deciday. Tau is not a good unit for angles in general, unless you have circles, or you need lengths of circumferences somewhere. (You want to paint your clock and calculate the amount of paint, or something.) Turn is the natural angle unit. And since the earth rotates 1 turn/day, the amount of turns is the same as the amount of days.