[NOTE: This post contains minor spoilers!]

There is a singular feature in the novels of The Expanse that we have tried very hard to express in the series: the idea that space itself is a character.

From the start, we’ve always attempted to portray the physical realities of life in space with as much, well, realism, as we can while still serving our dramatic needs, and whenever possible, we use physics itself to create drama in a way that almost every science fiction film or TV series tends to ignore, avoid, or just get flat-out wrong (the one film that got pretty much everything right was Stanley Kubrick’s 2001: A Space Odyssey—which was made almost 50 years ago).

I feel there have been lots of times we succeeded at this, other times we got things mostly right or not entirely wrong, and a few times where we failed. This is about one of the fails.

In Episode 11 of Season 2 (which airs this Wednesday at 10pm ET on Syfy), one of our characters (Alex, the pilot) has tucked his ship behind one of the smaller moons of Jupiter to keep it hidden from Martian patrol ships that have blockaded a base on the inner moon Ganymede, while his crewmates carry out a mission on Ganymede Station. When his crewmates become trapped, Alex has to come up with a risky rescue plan:

He plots a complex, gravity-assist (“slingshot”) trajectory to return to Ganymede without using the ship’s main fusion drive (which would expose him to detection by the patrols). Later, while he’s performing a maneuver, he barely avoids straying into the path of an unexpected ship.

The sequences are quite beautiful, well-acted and nicely directed, and the visual effects are gorgeous (particularly the immersive, holographic orbital trajectories of the Jovian moons, which are all scientifically accurate… at least I hope they are). And it’s a lot of fun to watch.

It’s also utterly preposterous.

But if we already knew that, then why did it end up on screen? Here’s what happened:

When we were working out this particular story line in our writers room, we needed a pick a moon to hide the ship behind, so off we went to Wikipedia, and we settled on moon #54 (Jupiter XLVIII), “Cyllene”.

Why Cyllene? Well… mainly because it was a girl’s name and it sounded pretty, which suited the scene and Alex’s character. It wasn’t until the picture had been locked and we were well into post-production that I realized we had a problem, due to one, simple fact that we hadn’t fully thought through:

Cyllene is really, really far away from Ganymede.

And that has big ramifications. The gravity-assist trajectory Alex (i.e., we) had devised would’ve in reality taken months to complete, but the sequence we’d created showed Alex slingshotting around several moons and getting back to Ganymede in a ludicrously short period of time.* (In a moment of derangement, I briefly considered fixing the problem by using VFX to make Alex’s beard appear longer each time we cut back to him, with empty beer cans and food bar wrappers accumulating around him to imply that a lot of time was passing in each cut. I’m only half kidding.)

By the time I was able to really focus on this sequence and understood the problems, it was too late. We were married to what we had physically shot on stage and the (extremely expensive) VFX already being built in our pipeline.** So I decided to let it go and wrote it off to dramatic license.

And that’s what bugs me more than anything else.

It’s far too easy in TV/film science fiction to ditch reality for (what you perceive to be or rationalize is) the sake of drama. In a fantasy space opera, this is forgivable, but for a show like The Expanse that prides itself on a realistic portrayal of space, it is not.

I did finally come up with an alternative sequence, one that would’ve better reflected reality and been far more exciting to boot… but by that time it was too late to change what we had. For the record, what I should have done was this:

1) Change the moon we picked to another one (with a pretty, girl’s name, of course) that was much closer to Ganymede (this would’ve required changing a few words of Alex’s dialogue, but that wouldn’t have been difficult to do);

2) Build the flight sequence around a single event: a complex trajectory adjustment around one moon, perhaps involving a dangerously close pass over the surface, with a limited window for Alex to complete the maneuver, which gets further complicated by the appearance of an unexpected patrol ship. Remember that terrific sequence in Apollo 13 in which James Lovell (Tom Hanks) has to hit a tiny re-entry window on manual control? This could’ve been as riveting like that.

As they say, that and a buck will buy me a coke (though I would much prefer a martini).

But stayed tuned. We’re planning another slingshot sequence, far more elaborate than this one, in season 3. I’ll make sure we get the science (at least mostly) right.

Naren Shankar

Executive Producer/Showrunner

The Expanse

*Ludicrous even by our own standards. One area where The Expanse consistently takes big liberties with physical reality is time-to-travel. The novels don’t do this, but they have the luxury of literary devices like interior monologue; in TV, you tend to cut out the parts where things aren’t happening. The series adaptation of Game of Thrones also often significantly compresses time and distances for the same reason, so at least we’re in good company.

**The accounting department at our studio often refers to the show as “The Expense”.