If you need to go to Saturn, the planet, in a big hurry, how would you do it? Oh, about 50 years in the future. John Sanford tried to solve the problem, in two ways: the traditional rocket or an ionic engine. No, anti-gravity or greater than light-speed have not been invented then.
Then he came up with an excellent reason to compel the super-powers to enter this race. Since there are two super-powers, there are, of course, the spy and politics sub-plots to enrich the main story.
Added some intense love and greed, mixed in some charming characters.
Now you have an excellent SciFi to enjoy. Yes, he is a skilled writer.