Sams Teach Yourself Java™ in 24 Hours, Sixth Edition

Watching the Skies at NASA

The first afternoon stop on the Java tour is a trip to NASA, a U.S. government agency that makes extensive use of Java. One of the most popular examples is SkyWatch, an applet that helps stargazers keep an eye out for orbiting satellites. Load it in your browser by visiting www.cadenhead.org/nasa; you are forwarded automatically to NASA’s SkyWatch site.

SkyWatch superimposes the current location and path of eight different satellites—which you can add or drop from view—over a globe of the world. The applet running in Figure 3.4 shows the SEASAT-1 satellite making a patch from the Bootes constellation to the Hercules constellation.

Figure 3.4. NASA’s SkyWatch applet monitors the location and path of orbiting satellites, ...