I finished reading the novel "Saturn Run" by John Sandford and Ctein. Putting aside storyline and content of the novel there was a very interesting Author's note that explains how the science portion was written and that it may be plausible.
Let me focus my question. Is it possible with our current VASIMR spaceship technology that a manned trip to Saturn and back to Earth is plausible?
The book gives a 6 month timeline from launch to Saturn and about the same time frame to get back to Earth. In order to avoid too much speculation I will stick with this time.
Please note any spoilers with the link I posted.
The United States ship is described below.
The Americans need something better. Enter the VASIMR engines. VASIMR stands for “Variable Specific Impulse Magnetoplasma Rocket.” “Specific impulse” is how rocket scientists refer to exhaust velocity. We didn’t make the VASIMR up. They’re being tested on Earth, fairly small ones. Ours are a lot bigger, and a little better-performing, but it’s fifty years from now. For a trip time of four to five months, we were able to get the ship down to a mass ratio of 10 with an exhaust velocity that varied from 35 up to 300 km/s. That’s about half the mass ratio we could come up with for a fixed-specific-impulse ship of any remotely plausible design.
Exhaust velocity is the magic number. As long as the total delta-vee you want is less than your exhaust velocity, the amount of reaction mass you need isn’t too bad.