End of Cassini’s Four-year Prime Mission

Todd J. Barber, Cassini lead propulsion engineer

With mere weeks to go in Cassini's four-year prime mission, I thought I would use a couple of columns to reflect on the journey to Saturn and the science highlights from orbit. It's hard to believe Cassini has been in space for over a decade, and many of us on the flight team actually started on the project before launch. My 30's came and went on this project, but in all honesty, where else would I have rather been?

There are scant few opportunities to reflect on a myriad of memories while still flying this productive and all-consuming mission, but I will take the time to do so today. I remember a sublimely beautiful launch through the pre-dawn Florida sky, with the gargantuan Titan IV launch vehicle swallowed up by a persistent, low-hanging cloud. Cassini's destiny would not be denied, though -- its triumphant emergence from the cotton ball illuminated from within soon followed. I recall babysitting a new spacecraft after its release from the Centaur, and, like all newborns, there were a few growing pains among us concerned parents. I remember a quick journey to Venus, a science warm-up for later glory at Saturn. I remember a monster Deep Space Maneuver to allow us to return to Venus for a second gravity assist, a wonderful "practice" burn for Saturn Orbit Insertion by happenstance.

I still fondly recall a frenetic summer of 1999, with a mere seven weeks between our second Venus flyby and a brief encounter of the home planet. Through 1999 and 2000, I reminisce about a speedy sojourn through the asteroid belt, a wonderful and scientifically productive encounter with Jupiter, and then settling in for the long cruise to Saturn. Through the first few years of the new millennium, I remember endless meetings and preparations for Saturn arrival. I recall an astounding encounter with Saturn's oddball satellite, Phoebe, and the incredible resolution in the imagery vs. Voyager photos, just a few weeks before getting to Saturn. Finally, with glee I remember a picture-perfect rocket firing on July 1, 2004, allowing this incredibly capable robot the opportunity to become the first artificial satellite of the ringed planet. Truly, Cassini's voyage to Saturn was one for the ages.