EXAMPLES OF ACTUAL DEEP SPACE TRAJECTORIES
To illustrate the reality of inter-planetary space travel based on the principles we discussed above, we show here a few of the actual missions that have been carried out successfully.
CASSINI to Saturn
This trajectory shows multiple flyby’s requiring a favourable configuration of planets, in particular for the last gravity assist past Jupiter. Launch windows are usually quite specific when gravity assist manoeuvers are needed. It took Cassini 6.7 years to reach its destination Saturn. Since its arrival in 2004 most of Cassini’s manoeuvring has been done with further gravity assist at Saturn’s moon Titan.
The graph depicts the speed increases (∆V’s) during the trajectory towards and while at Saturn. After mid 2004 (arrival at Saturn) the frequent ∆V’s are due to flyby’s at Titan. This programme would not have been possible with Cassini’s own propellant. The highly successful mission continued until the end of 2017 when Cassini was steered into Saturn.