The novel has no information regarding that, whereas the film does show a post-script 5 years laterand there is another mission with some of the same crew
That crew is identified as Ares V. Given that the dialogue makes it sound as though the most recent mission was Ares 3, it would seem that they just skipped 4.
Vincent: "The Ares 5 team will rendezvous with the Hermes...from there they will have 414 days of space travel ahead of them."
Reporter: "Have the goals changed from the previous mission to the Ares 5 program? And what do you hope to achieve this time around?"
Vincent: "Well, no. The goals have always been the same for the Ares program. This time, of course, we hope to bring all the astronauts back at the same time."
TV Reporter: "There you have it, 5 years after the rescue of Mark Watney, an Ares V is on its way to Mars"