As an astrophysicist, my world revolves around the wonders of space and the mysteries of the universe. This means I can be a tough critic of science fiction books and films that explore these topics.

Science fiction is not monolithic. There are, in fact, two major sub-genres that divide sci-fi — hard sci-fi and speculative (or soft) sci-fi — and most of the time, the delineation between the two is ...