When Stephen Baxter had been writing for a few years, there was an opinion amongst many sf readers that “Baxter can do Big Dumb Objects, but he can’t do characters for toffee.” Then along came “Voyage” and blew that opinion out of the water.
The premise – an alternate universe where Kennedy survived assassination (just), and, invited by Nixon to the Oval Office to share in the reflected glory of the telephone call to the Moon in 1969, steals the show by publicly calling from his wheelchair for the next goal to be Mars, and no-one has the heart to raise any practical objections.
The story then develops as NASA devise a plan and begin to work towards it using 1960s technology. The characters have stepped straight out of “The Right Stuff” but they are beginning to get out of their depth. There are accidents, and there are human stories as the double standards of using Nazi rocket science come home to roost. Finally, the mission is accomplished, but at a price. And with a twist that shows that the alternate history Baxter portrays is truly different to ours.
(Baxter developed the universe of this novel in a short story [not collected, AFAIK] where a British attempt to put a man – Roly Beaumont, top test pilot of the 1950s – into orbit fails…)