Earth revolves around the sun once per year. The axis of rotation points in the same direction throughout the yearly trip.
In order to illustrate how much sunlight different parts of Earth receive through the year, this model shows our planet much larger and closer to the sun than it actually is. Examine the model carefully to compare the amount of sunlight the Northern and Southern Hemispheres receive in March, June, September, and December.
Click the image to see the animation. Use the movie controls to step through the sequence or replay it. Click the left button to show or hide the names of the months represented by each portion of Earth's orbit. Click the right button to see the model from a different perspective.