December Solstice

North end of earths rotational axis is away from the sun.

On December 21 or 22

June Solstice

North end of earths rotational axis is towards the sun.

On june 20 or 21

September Equinox

North end of earth rotation axis leans along earths orbit.(away from sun)

September 22 or 23

March Equinox

North end of earths rotational axis leans along earths orbit.(towards sun)

March20 or 21