Gravity

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Gravity

Hi!

I really enjoyed NEO Scavenger and I'm quite looking forward to playing Ostranauts :-) From what I saw on your Youtube-Channel, the game looks really promising. There's just a little something that I might not have understood by now:

You've said that you didn't want to use artificial gravity in your game because you preferred to stick to less Sci-Fi physics. But given the artwork that you revealed so far, your ship-design with sofas, tables, and ashtrays relies on gravity for things to stay where they belong. You wanted to solve this by constantly accelerating your ships if I understood that correctly.
If I got that right, wouldn't that lead to some logical problems itself? For example, the amount of fuel you would need to travel would need to be extremely huge, because you cannot have any phases with constant traveling speed (that doesn't need much fuel because the ship just keeps its momentum). You need to constantly fire your main engine to keep up gravity, either accelerating or deaccelerating for the whole trip. Plus, you need to change from acceleration to deacceleration at some point. On that point, you would need to flip the ship around, so you can deaccelerate using the main engine. And at least when you do that, you would have a short phase without gravity.

Since I infer from the looks of the gameplay that you are probably aware of this, how do you solve it? I'm just curious :-)

Good question! And you're right. This assumes constant acceleration, with a flip to deceleration halfway. ("Flip and burn" in the Expanse parlance, which is a fictional universe sharing a lot of the same tropes.)

Using more efficient ways to travel in space tends to mean a lot of waiting. Waiting for celestial windows to open, and waiting during the long coasting periods. Waiting on the order of months or years for many cross-System trips.

To make travel a bit more like days and weeks, we'd have to be accelerating on the order of 1-2g. (10-20m/s2) And conveniently, that also means we have an artificial 1-2g gravity on the ship during travel. (Which is good for crew health, and also allows us to use more familiar deck designs.)

But you're right that we have to start slowing down at some point, and during that maneuver, we have zero (or worse, chaotic) gravity. During this time, crew would have to brace or strap-in. And anything on the ship would need to be stowed or otherwise secured.

The good news is that this tends to be a very short period mid-trip, plus maybe some maneuvering time at the beginning and end. Similar to how we experience air travel: strap-in and put your seatbacks and tray tables up during taxi, take-off, landing, and turbulence.

As for the science behind a drive that allows this kind of sustained acceleration, it's ultra efficient He3-D fusion. With water as an optional propellant.

This is where the fiction is biggest: the fusion reaction here is technically possible, but way beyond the reach of current tech. It also requires shielding and heat dissipation that might be unrealistic in such a small package. This blog post explains some approaches which might reconcile the science with the fiction.

We're bending physics a bit here for fun/cool factor :) But we're trying to be honest enough to make things seem plausible.

Finally, there is one special thing about the NEO Scavenger universe which explains some of these fictional elements. I try not to lean on it too much, but it's a core feature of the world which makes things like the supernatural possible.

Spoiler: Highlight to view
Namely, if enough people think something is true, it starts to become true.

Dogmen appear in Michigan because someone thought they see them at the edges of the wilderness, the rumor spreads, and eventually that becomes reality. Whether it's actual dogmen, hallucinations, mutations, or whatever, they become a fixture in the world.

Similarly, science plods ever forward, producing new tech that once seemed impossible. Enough people start believing efficient fusion is possible, and work towards that goal, that it incrementally starts to become possible. Whether it's by gradually understanding more about fusion, or by some "magic" discovery, it starts to become common knowledge, and eventually, common tech.

All the myths are true. All the conspiracies are true. All of the tenets of science are true. Which ones are more true depends on who has the most backing :)

Dan Fedor - Founder, Blue Bottle Games