Sci-fi has always had a love-hate relationship with physics as a genre. The terms “soft” and “hard” science-fiction often represent how closely a given sci-fi show, book, movie, or other medium tries to capture the scientifically accurate nature of how objects and technology function in space. While many people have their preferences (to the point of having blood-curling debates on whether writers should be shot for having sound in space) the choices sci-fi makes to be accurate or not affect the overall tone and presentation. So let’s take a look at this.

First, let me say right off the bat this article isn’t about which sci-fi is better because it is “authentic” or not. Let’s leave that discussion for the late, alcohol-fueled nights where such matters really seem important. This is a discussion about how these choices influence what a sci-fi show or movie is. The choice may seem trivial, but it can affect how the story and its characters progress, and how we remember and judge the narrative.

Second, I’m also staying away from printed media like books and graphic novels. While some popular sci-fi novels and series explicitly describe how their universe obeys or disobeys the laws of physics, most of them have you fill in the blanks through your imagination. TV shows and movies, however, can’t help but lay everything out on the table.

To understand how a starship flying like a jet fighter in space creates a different story than one that obeys the laws of floating things, it helps to know how things really should act.

A Brief Lesson On Astrophysics

The details of how objects move around and operate in space are insanely complex. The math alone is enough to make my head explode three times over, congeal itself Terminator-style, then explode three more times just for good measure. So we’re going to avoid the complicated graduate-level lesson on astrophysics and just touch on the basics.
Space is full of a lot of nothingness. It’s not a complete vacuum like most people assume. You have things like radiation, dust particles, gas clouds, and other things that generally want to murder your ass (and that’s not even getting into things like dark matter and dark energy). But, for the most part, objects floating in space don’t have much resistance.

This means they like to travel and keep traveling. Newton’s law of objects in motion like to stay in motion pretty much applies. If space truly was empty, astrophysics would be fairly simple: anything that moves will continue to move in a straight line until it doesn’t.

Solid objects, gravity, solar radiation, and more mess with this “straight and narrow” flight model, which usually either creates complete destruction or what we know as an orbit. Objects that move around other objects move in circles and ovals. If you want to fly around in space, you have to think in circles and ovals as well.

For example, let’s say you want to get to the moon. Conventional thought would say build a rocket, pointed towards the moon, hit the gas, then ride it out. Instead, people much smarter and more experienced in these matters know that the best way to get to the moon is to draw a bunch of different circles and ovals around Earth, the moon, and the space in between.

This means you have to think about things like gravity and speed. The faster you go, in general, the bigger your orbit will be assuming you don’t miss your destination and fly off into the dark abyss. Slower speeds will decrease in orbit, which is why modern spacecraft have to turn their butt in the opposite direction and release a massive fireball fart in order to reenter the atmosphere.

If you’re just waking up by now because all this put you to sleep, here’s the bottom line: objects in space don’t move the same as on Earth. Why is this important?

The Aesthetics Of Movement

Think about your favorite science fiction TV show or movie battle. For me, one of the best is the battle between rebels and imperials fighting around the second Death Star in Return of the Jedi. Little ships flying around each other, dogfighting, exploding in glorious displays of fiery death, tend to characterize what Star Wars is known for. George Lucas, when creating the visual effects for the original trilogy, referred to old dogfighting footage from World War II for inspiration.

Star Wars wouldn’t be the same, in fact, if recognizable ships like the Millennium Falcon flew around like modern rockets and space shuttles. If Han Solo ever uttered the phrase “prepare for the retrograde burn,” most of the theater audience would have collectively stood up, tossed their concessions up into the air, and started to embrace each other to cry.

Many sci-fi shows and movies follow this style of movement: Star Wars, Star Trek, Galaxy Quest, Armageddon, and more. In the days before fancy CGI or even practical special effects, spaceflight was even more simplistic. However, as the production technology has advanced over the years, TV and filmmakers have had more options at their disposal to define how their sci-fi universes look through movement.

Sticking To Reality

It’s hard to argue that any sci-fi show or series is complete, 100% adhering to reality. The basic idea of science fiction is to show what isn’t necessarily possible in the present. But for decades, many popular examples of science-fiction have avoided trying to recreate how objects move on Earth and have embraced the narrative challenges of actual spaceflight.

A lot of modern science fiction has started to rebel against the conventional storytelling tropes that made series like Star Trek and Star Wars popular. While the Battlestar Galactica reboot was showing us sex, violence, and nudity in space was a good thing, it was also redefining science-fiction dogfights. Instead of swooping in with the sounds of screaming engines, their fighters floated and rotated around each other with the subtle patter of gunfire vibrating through the hull. Before that, Firefly showed us what true silence in space felt like as the Serenity floated along in the abyss.

Even today shows like The Expanse continues to push the envelope of accurate spaceflight. That show, in particular, is one of the only to recognize the influence of G forces on the human body. That’s why their people fly with the engines to their feet. Their ships are like big giant skyscrapers with rocket engines attached to the bottom.

There are too many examples of this kind of change to even begin to appreciate the influence these choices can have on sci-fi. There isn’t necessarily the right choice in the matter. Viewers certainly have their preferences, but it’s hard to say that Star Wars is better than Battlestar Galactica, or vice versa, simply because of the way ships accurately or inaccurately move.

Instead, the important thing is the influence these decisions have on the overall look and feel of science fiction. Since TV shows and movies are visual in nature, movement is one of the underestimated influences that will shape how viewers experience the story.

How a ship flies around in space is just as important as how a dancer moves around on a stage.