[Etienne]

Etienne asked the Naked Scientists:
   
What technology is used in the latest travel to Jupiter taking 5 years? The increase in speed capability seems to have been enhanced significantly. What has changed?

What do you think?

[Soul Surfer]

The time it takes to perform a journey around the solar system depends on how much energy you are prepared to put into getting there and of course slowing down when you have arrived if you are not going to go zooming by.  The Voyager probes were fly bys and intending to leave the solar system so they went very quickly.  Even then there were severe worries in the design about the life of critical electronics (still using some tube technology) not being long enough to do the full journey.  As it happened they both worked very well.  More recent probes like Galileo involved orbiters  and so had to approach much more gently to avoid the need for large quantities of fuel to slow down when you got there they also used gravity assist from other planets and so had to go the long way round to pick up the "free" energy. 

I am not sure which mission your five year trip time refers to but the recent pluto spacecraft got there much quicker.

[CliffordK]

There has been some discussion about Plasma Rocket Engines 

They are still experimental, but undoubtedly we'll see similar technology in our future deep space probes.