Equinoxes or solstice

 

• A solstice occurs when one of the Earth’s poles (today, it’s the north) tilts toward the sun at the maximum angle. The two solstices, in December and June, mark the beginning of winter and summer and give us the longest days and nights of the year.
• Equinoxes are essentially the opposite of solstices. Deriving from the Latin for “equal night,” the equinox is when the sun is directly over the equator, leading to roughly the same amount of day and night. Spring and fall begin on equinoxes.