Nice applet, i like 3d panel, well i modified applet that already created by prof Hwang, and but is not 3d is 2d [url=http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2244.0]http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2244.0[/url]

[img]http://www.phy.ntnu.edu.tw/ntnujava/index.php?action=dlattach;topic=2245.0;attach=4338;image[/img]
I add image to the earth and do a slow rotation for earth, but i believe im gonna to add more options may also add 3d panel, need only some time to study more about satellite motion. :)