Here is a Web site that is at least intended to be basic ("for Dummies" might not apply to even basic satellite dynamics, sort of like the "Basic Topology" text I had as an undergrad ;) http://www.jpl.nasa.gov/basics/ I echo Stephe Leake's sentiments (envy? ;) for being in an organization that is using Ada. Is that an uphill battle, a straightforward analysis & decision, or is it to the point where Ada is just assumed to be the best language for the problem at hand? Mike ----------------------------------------------------------------- Michael Stark Lead Researcher, Software Engineering Laboratory Phone: (301) 286-5048 Code 581 Fax: (301) 286-5719 Greenbelt, MD 20771 e-mail: [log in to unmask] web: http://www.cs.umd.edu/~mstark -----------------------------------------------------------------