I won’t start an argument about the definition of “hard SF” or the state of scientific accuracy in fiction, but here are a few handy rules for science-fiction writers who want a quick test of real-science groundedness.
I call them Joi’s Laws, because SF writer Joi Weaver put them so well. (The headlines are her laws; the rambling context is mine.) Each one is a challenge: avoid this common crutch when starting your own story. Think of them like the Bechdel Test for solid science.
No FTL Travel
Space is big, and ships are slow. That’s the reality for at least another century, so embrace it. Faster-than-light travel lets your characters hop from star system to star system, but what are you really gaining? How is a rock around Epsilon Eridani inherently more interesting than a rock in the Main Belt?
Even if your story is set in the far future around a far star, FTL travel is dispensable. Joss Whedon didn’t need it for Firefly, and his (solar-system-sized) universe was packed full of interesting locations.
No Aliens
Everyone knows it: aliens in most stories are just humans with funny foreheads. Even the most unusual aliens in the most mind-bending stories turn out to have mostly human attributes, because a) it’s hard to imagine anything truly alien, and b) it’s harder to relate to truly alien aliens. So stop trying. Humans and animals have bizarre enough variations to fill a century of stories.
My own corollary: No Monsters. Monster stories are great and all, but 99% of new sci-fi is already cluttered with zombies, mutant viruses, and killer robots. Next time you need something terrifying, how about the interplanetary DMV instead?
No Artificial Gravity
This one is tough even for me. I’m obsessed with gravity, and I honestly believe we’ll be a second-rate spacefaring species until we learn to control it. Still, no one is close to controlling gravity even a little bit, so spaceships with a solid one-gee field working at all times are still pure fantasy.
Besides, fifty years of astronaut hijinks teach us that weightlessness is one of the best things about space travel, and we haven’t yet explored the spectacle of low-gravity sports. The only reason your characters would actually choose to be in a one-gee field (occasionally) is due to health concerns, and a treatment for bone loss is much more believable than gravity control.
“It’s more a guideline than a code.”
Good stories can still be told if they violate Joi’s Laws. (I’m going to see the next Star Trek film just like everyone else.) They’re not a guarantee of a good story, either. If you want to tell a *new* story, though, keep these in mind to give yourself a bit of a real-science challenge.