Apparent movement of the Sun March equinox
in apparent motion on day of equinox, sun s disk crosses earth s horizon directly east @ dawn—rising; , again, 12 hours later, directly west @ dusk—setting. march equinox, equinoxes, characterized having equal amount of daylight , night across latitudes on earth. due refraction of light rays in earth s atmosphere sun visible above horizon when disc below limb of earth. additionally, when seen earth, sun bright disc in sky , not point of light, sunrise , sunset can said start several minutes before sun s geometric center crosses horizon, , extends equally long after. these conditions produce differentials of actual durations of light , darkness @ various locations on earth during equinox. notable @ more extreme latitudes, sun may seen travel sideways considerably during dawn , evening, drawing out transition day night. @ north or south poles, sun appears move steadily around horizon, , above horizon, neither rising nor setting apart slight change in declination of 0.39° per day equinox passes.
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