Spring Equinox: An equinox is an event in which a planet’s subsolar point passes through its Equator.

Article

Although the equinoxes are as close to this phenomenon as happens on Earth, even during the equinoxes day and night aren’t exactly equal. This is largely due to atmospheric refraction. Atmospheric refraction describes the way light seems to bend or deviate from a straight line as it passes through Earth’s atmosphere. Atmospheric refraction is a result of increasing air density, which decreases the velocity of light through the air. Due to atmospheric refraction, we are able to see the sun minutes before it actually rises and sets.