Help button: This button will open a window with help information.
Calculate comet speed - use this button to open a pop-up window that will help you calculate the comet's speed
Calculate comet's size - use this button to open a pop-up window that will help you calculate the comet's size
Reset: reload the applet and reset the parameters.
Rewind: press and hold to advance the applet in reverse.
Pause: temporarily stop the action in the applet.
Play: begin or resume the action in the applet.
Fast Forward: press and hold to advance the applet.
End: advance the applet to its end.
Speed: click to select the number and input a higher number to increase the speed of the rewind and fast forward buttons.
Slider bar: shows the progression through the animation.
Drag controller: click and drag over this symbol to reposition the controller buttons within the applet frame.
Collapse button: click this button to collapse controller button.
Using the applet
This applet has been designed to help students gain an appreciation for the vast scale of the Milky Way Galaxy. The applet begins by showing a representation of the Milky Way. As the animation progresses, the field zooms in on the solar system and then on the Earth itself. At the top of the applet is an approximate size which will correspond to the given field of view. Remember that one AU is equivalent to the distance between the Sun and the Earth.
One can clearly observe the vast differences between the sizes of the Milky Way, the solar system and the Earth.