Table of Contents

Phases of the Moon

Module 3: The Earth and the Moon

Button controls:

• (1) Help button:
  • This button will open a window with help information
• (2) Controller buttons:

• (A) Reset: reload the applet and reset the parameters
• (B) Rewind: press and hold to advance the applet in reverse
• (C) Pause: temporarily stop the action in the applet
• (D) Play: begin or resume the action in the applet
• (E) Fast Forward: press and hold to advance the applet
• (F) End: advance the applet to its end
• (G) Speed: click to select the number and input a higher number to increase the speed of the rewind and fast forward buttons
• (H) Slider bar: shows the progression through the animation
• (I) Drag controller: click and drag over this symbol to reposition the controller buttons within the applet frame
• (J) Collapse buttons: click this button to collapse controller buttons

Using the applet:

This applet has been designed to help students visualize the phases of the Moon.

The key to understanding the phases of the Moon lies in the arrangement of the Sun(6), Moon(4) and Earth (5). Half of the Moon is always lit by the Sun, but the lunar phase (3) will change depending on where the Moon is in its orbit.

* Remember that this is a two-dimensional model, and eclipses do not occur in each orbit because the Moon's orbit is slightly tilted. For more information about eclipses, refer to the eclipses applet.