C.T. Russell 
Cassini-Huygens Mission [PDF ebook] 
Volume 1: Overview, Objectives and Huygens Instrumentarium

The exploration of the planets is the modem counterpart to the exploration voy- ages of old. To reach the new world Columbus had to secure funding from Queen Isabella, outfit his three ships and set sail on a long journey. To explore the Amer- ican Pacific Northwest, Lewis and Clark had a similar task of obtaining funding, purchasing equipment and going to points unknown, even though their path was across land and not sea. Today our journey is through space, rather than across land or sea, but we still travel with ships, now spaceworthy craft, rather than seaworthy. Our spacecraft are smaller than the ships of yore, crammed with electronics rather than provisions because man cannot go along on these journeys. We now rely on robots to be our eyes and ears at these distant worlds. Nevertheless, some aspects of exploration have not changed over the centuries. People are still fascinated by these unknown worlds and desire to explore them, and the process of obtaining the large sums of public moneys to finance these journeys still requires much pleading with authorities.