Interaction
How does light shift my body-clock?
The interactive graph below demonstrates the effect of light exposure upon your body-clock. Time of day is on the horizontal axis and the vertical axis measures "dayness" (for the sun's curve, think "height in the sky" and for the body-clock's, think "day-specific activity").
Click anywhere on the graph to simulate light exposure at that time of day (or night). Hovering will compare your body's expected time of day (courtesy of your body-clock) with the actual time (courtesy of the sun).
Don't be alarmed when you find that light during the day shifts your body-clock. The slight leftward shift in the morning is countered by a rightward shift in the evening.