When is it real worldbuilding and when is it simply making the trees blue, the sky green, and calling coffee "glerp?" The panel looks at good and not so good examples of world building.

In early SF, the planets of the solar system were simply exotic locales for adventure. The next generation of SF writers -- Heinlein, Clarke, and others -- tried for more realism, but their solar systems were very different from the one we know today. What are good examples, and how do the new limitations on what writers can do and still be realistic make for good SF.

Hear a "trialog" by longtime SF writers as they revive their periodic talk on life, the universe and everything, especially science fiction.