Editor's Note for Asteroids Have Seasons, Too

In this orbit diagram, the solstices and equinoxes are marked as if they are points in space located along the orbits of Eros and the Earth. Equinoxes and solstices are actually points on a celestial sphere which has the Earth (or Eros) at its center. For example, the Sun passes through the June solstice when it reaches its maximum northern declination as seen from our planet. What is meant when the Earth is shown at an equinox or a solstice in the diagram is that the Sun appears to be at that corresponding point in the sky as seen from the Earth.