Oh and btw for the radiators before the reservoir, the devs actually explained in an interview that they just vent the excess heat from the simulation. The water system around the stranger actually seems to serve a dual purpose of cooling the simulation and also reminding the owlks of their home (not well though 😢)

you're forgetting one important factor about the solar sails

they''re green

just like the light sensitive mechanisms inside the the ship
the raft 4 control pillars, the doors, the elevators etc

their sails arent just regular solar sails, its a light sensitive material that applies some sort of force on nearby things when exposed to light

so my argument would be the solar sails are plausible with this mysterious material they use

I think the cloaking field is intentionally, selectively, letting only the light from the sun inside. When inside the field, you can only see the sun, no other stars or planets. Inside the Stranger, the planets and stars are visible because they're rendered and displayed on the "window" screens.

Cool! Now rank all the planets in our solar system based on how realistic they are!

Spinning is so much cooler than not spinning.

Not to take away from the video but going this in-depth on The Stranger is funny because to get there you fly in a spacecraft made of wood and can survive the vacuum of space so long as you have a potted desk plant next to you.

Edit: Should have watched the entire video before typing this lol

About the centrifugal gravity, in outer wilds the planets generate a completely disproportionate gravity, it is entirely posible that a good chunk of the gravity comes from the weight of the stranger itself and the rotation makes the slight adjustments necessary (I am not exactly sure about how the gravitational pulls interact with each other inside a cylinder though)

In terms of you mentioning the super sci-fi conversion of light into energy, I think the Owelks are shown through their technology (i.e. the rafts and doors) to convert light very efficiently into energy, so the solar sails may be very efficient in converting the light from the sun into motion, pushing the stranger forward. I'm not a physicist, though, and I think it's more a case of it making sense than it being realistic.
Good video though, very interesting, and I always love a bit of Outer Wilds content.

Obligatory corrections/elaborations comment:

1) Some commenters have pointed out the no-slip condition isn't enough for the river to fully match the rotation of the ring itself, and I think that is true yes. Since the layer of water is like 10m thick the angular rotation of the Stranger (0.05 rad/s) would have the top of the water flowing 0.5m/s slower than the bottom, so the river might flow just very very slowly (no where near the speed in game). You'd need more than a full loop for the water to circle the stranger even once, so some energy source is still required to match the speed in game. Would be really cool if somebody went and solved the navier-stokes equations in a rotating reference frame and then we will all finally know for certain! (not it)
2) The solar sails are green

The stranger being able to float would be explained if they just had kept the sails slightly open, since it could be assumed the acceleration from radiation pressure and gravity of the sun cancel out.

5:06 One thing I was disappointed by with the artificial gravity is that I couldn't take advantage of the gravitational Coriolis effect that centrifugal gravity produces to hover into the center. My scout did, but I couldn't.

Nice video! Worth noting that the ship/player/scout also aren't affected by the sun's gravity when within the Stranger's cloaking field, so it would seem the cloaking field somehow has something to do with the Stranger not being pulled into the sun (also once the Stranger starts moving away from the sun it takes the cloaking field with it, which lets the ship start falling. That's how "lucid dreaming" works in speedruns)

I know this is one step away from "it's video game magic, don't worry about it", but my headcanon states that Outer Wilds doesn't take place in our universe, it takes place in the next one.  After someone reaches the eye in our universe, the Outer Wilds universe is created.  This has similar looking physics, but is tweaked in different ways to allow a tiny little solar system to exist, and light speed/light energy being modified, a few trees being able to support a full village of Hearthians etc.  Still doesn't explain everything, but would explain most of these issues.

I always assumed those radiator things were heat sinks, and the whole river system functioned as liquid cooling for the "computers" running the virtual world.

Up to 15:21 this felt way too serious to be a Xen video. But you made it right in the end!

I think the cloaking field eclipsing the sun instead of cloaking against it is intentional in order to use the solar energy it lets through as a power source, for both on board technology and the solar sails.

I got eaten by an owlk

You're forgetting one important fact about the solar sails
They're made of the same material used on the rafts, so they likely generate much more energy from photon interaction and then reflect that back.
How the hovering works is likely the solar sails having a constantly applied amount of light, such as the potential of lighting in the solar sail protectors to generate a force small enough that it doesn't fly away but large enough that it hovers above the sun.

Solar sails turning light directly into kinetic energy is literally magic. The amount of energy it takes depends on your frame of reference, and the only way for it to not be creating energy from any frame of reference is for it to generate the same amount of thrust as it would if it just reflected the light back towards the sun.


It is possible for it to send a different pattern of light in every direction to look invisible. You basically just need to cover the surface with cameras. The problem is that it's going to be generating some heat, which has to be radiated away, and is really easy to detect against the cool sky. With sufficiently advanced technology, they might be able to send the waste heat all in one direction so only someone passing from that side can see it. But the Stranger is doing the exact opposite of that. If you go opposite the sun, you not only don't see all the waste heat it should be generating, you don't even see the sunlight. It's absorbing more light than it's emitting, with the extra light going nowhere. The only way this can work is if it really is emitting all that heat outside the visible spectrum, and the intelligent species that built spaceships just never built infrared cameras that could see it. But it's crazy that they'd go through all that effort to camouflage it and hope the natives just never build infrared detectors.

Also, if it's sending all its waste heat away from the sun, that would push it towards it. In order for it to keep hovering like that, it should be sending quite a lot of light towards the sun, making it clearly visible to anyone between it and the sun.

What if the solar sails just have green humor and thats how they work