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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.

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closed as primarily opinion-based by kim holder, Fred, Hohmannfan, TildalWave, GdD Mar 14 '16 at 10:19

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ I can understand why you are interested, but this is too much to handle in one answer, and also it would be necessary to speculate a lot, which we try to keep to a minimum. If you are really interested in knowing about this, try breaking it up into several questions that can be answered in a page or so of text. Both kinds of engines do exist, they can be talked about if you want to ask about them. There are many unresolved health questions concerning deep space crewed spaceflight. That is best handled separately too. $\endgroup$ – kim holder Mar 14 '16 at 2:56
  • $\begingroup$ @kimholder I will edit the question for brevity. $\endgroup$ – Gandalfous Mar 14 '16 at 3:02
  • $\begingroup$ When we get people to Mars we'll have a better idea of when & how we'll be able to get people beyond Mars to places like Saturn $\endgroup$ – Fred Mar 14 '16 at 4:33
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    $\begingroup$ This is entirely possible technically and entirely impossible politically. Without another cold war + space race, the space program will never obtain necessary funding for the required research. But should some political miracle happen and both the funds would appear, at amounts similar to the Apollo program, and simultaneously some motivation to pick Saturn as the destination over many other, more attractive destinations, yes, we could do it in 50 years. But in the current political climate this is not going to happen. $\endgroup$ – SF. Mar 14 '16 at 14:09
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    $\begingroup$ @Puffin: Seems like a job for a nuclear reactor... and if you pack one on board you might go with NTR instead, to simplify the matters. Nevertheless, 12 months roundtrip sounds is an awfully tight schedule requiring a very non-optimal transfer. 6.48 km/s at 9.2 years with a Jupiter flyby, 15.2 year at 6.89km/s for a round-trip. $\endgroup$ – SF. Mar 17 '16 at 13:06