 For times in the afternoon, the Vilna Gaon's times are earlier, and are almost universally followed.These are called "seasonal" or "variable" hours because they depend on the length of time between sunrise (or daybreak) and sunset (or nightfall), and those vary through the year.Near New York, for example, a "seasonal hour" based on the Vilna Gaon's calculations lasts around 45 minutes near winter solstice, around 60 minutes near the equinoxes, and around 75 minutes near summer solstice.