Evocative, metaphorical and sensuous
Evocative (and strange)
Poetic language is not usually something we associate with sci-fi writing, but Bradbury has got the evocative language down. He'll often use a strange or unexpected word to conjure up a whole set of associations in the reader.
For instance, when a Martian goes running over the sands, Bradbury describes him as running like "wild calipers" ("The Earth Men," 75). Calipers are a device used to measure distance. There are a couple of different designs, but they often look something like this. In other words, not something usually associated with running, and it makes the Martian seem weirdly clumsy and long-legged. What's awesome is Bradley doesn't have to say anything boring like "the Martian was clumsy and had long legs." He just—evokes it. Evocatively.
For another example, Bradbury describes the sand ships as "preening the sea bottoms" ("The Off Season," 111). "Preen" means to clean or smooth down—birds preen their feathers with their beaks. So simply by using the verb "preen," Bradbury is making a little comparison between the ships and bird's beaks, without using the word "bird," almost as if the ships are somehow arranging the sand into pretty lines.
Figurative and Sensuous
So, we know Bradbury knows how to use words. He also sure knows how to write a sentence, particularly ones that use figurative language to help the reader see, smell, or hear. For instance:
He felt something in the seat behind him, something as frail as your breath on a cold morning, something as blue as hickory-wood smoke at twilight, something like old white lace, something like a snowfall, something like the icy rime of winter on the brittle sedge. ("The Off Season," 81)
That's the description we get when a Martian is standing behind Sam Parkhill. Instead of just saying "There's a Martian behind Sam, and it gives him a weird feeling at the back of his neck," Bradbury gives us this list of comparisons, or similes, that evoke a certain feeling. We get the sense of something insubstantial—something so light that it might just blow away in the wind. (Which is what happens after Sam fires his gun.)