|AC: What makes space opera different from hard sf, military sf, or planetary romance? |
JC: The Wikipedia entry on this is quite good, and I’ll be cribbing my answer from there: http://en.wikipedia.org/wiki/
Basically, the primary difference between space opera and planetary romance is that the former emphasizes space travel while the latter emphasizes what takes place on alien worlds. For my part, alien worlds exist in space, so I tend to mix the two up. I read Doc Smith and Edgar Rice Burroughs at about the same time, and tend to classify the former’s Lensman stories with the latter’s John Carter, Warlord of Mars stories. They’re technically different but close enough in tone to comfortably co-exist.
There is a clear difference between hard SF and space opera. I think space opera is science fiction with a lessened emphasis on rigorous science and a greater emphasis on adventure, characterization, and sprawling scale. In Star Wars, George Lucas did a great job of suggesting advanced technology (anti-grav hovercraft, energy beam weapons, light sabers) without going into any great detail how any of those technologies worked. He simply used them (consistently, for the most part) in the telling of his stories. (There were a multitude of other design flaws, however, which John Scalzi recently exposed in a column at AMC.)
Military SF strikes me as a subset of space opera and science fiction with parts that overlap between the two. Walter Jon Williams’ Praxis trilogy depicts large-scale space battles with futuristic weapons, however, the science he uses is quite rigorous and consistent. Take the Ender’s Game books by Orson Scott Card for another example. They clearly contain military SF elements. They just as clearly contain space opera elements. And so one can be a fan of the one sub-genre without being an explicit fan of the other and still enjoy the work.