Ray Bradbury was the least sciencey of the ABC (Asimov, Bradbury, Clarke) science fiction writers. His stories were gossamer fables not hard-edged puzzles. The Martian Chronicles were not so much a tale about traveling to Mars as they were about trips to a Mars. One that didn't exist so he had to invent it. It was a wistful lonely Mars, not a place of adventure and discovery. Bradbury brought poetry and beauty to a genre prone to Hemingwayesque simplicity. He bridged science fiction and fantasy and horror in ways no later writer has managed to successfully meld.
His legacy is permanent as Fahrenheit 451, along with 1984 and Brave New World, is one of the most important dystopian novels of the 20th century. It's a book that is more true and more real and more frightening than when it was first published.
Bradbury brought literature into science fiction and vice versa. He transcended the genre. As Kurt Vonnegut once said, the problem with being put in a drawer called science fiction is that too many critics mistake it for a urinal. Bradbury escaped that pigeonhole and taught the world that science fiction could be lyrical.
He inspired inquiry and passion. None more so than in this video:
I even forgive the video its (literal) slap at Kurt Vonnegut. While the video is a joke, it rings true because Bradbury was a staple of high school reading lists kids actually enjoy. And his writing crosses gender lines in popularity. He was a pioneer and a guiding light and he will be missed but not forgotten.