What causes the equinox to occur twice a year?

An equinox is an event that takes place in Earth's orbit around the sun. ... The equinoxes and solstices are caused by Earth's tilt on its axis and ceaseless motion in orbit. You can think of an equinox as happening on the imaginary dome of our sky, or as an event that happens in Earth's orbit around the sun.

Explanation:

tilt and orbit of the Earth combine in a way that the axis is inclined away from the sun

Explanation:

We have an equinox twice a year. The Spring and Fall equinox. An equinox occurs when the tilt of the Earth's axis and Earth's orbit around the sun combine in such a way that the axis is inclined away from the sun.

This happens when the air has a lot of moisture and when the temperature is low (because in this way the water in the air condenses). So if a weather station predicts that warm humid air will pass over much cooler land, the precaution must be to use healights and drive slowly because it will probably be dense fog.