Hi everyone!

I've been working on a personal worldbuilding project called The Orbital Age, exploring a future where humanity increasingly builds artificial habitats rather than attempting to terraform planets.I thought this community might appreciate some of the ideas, particularly the engineering challenges involved.

This is CR-Meridian, a fictional rotating habitat approximately 40 km in diameter and 4 km wide.

It's part of a habitat concept I've been calling a Taylor Orbital.

Rather than having an entirely open interior, the populated sections are protected by a heavily armoured outer structure. Ordinary streets sit beneath a structural ceiling roughly 30 metres above ground level, with artificial skies. Taller buildings extend into an enclosed upper volume, and some areas have protected views into space.

The idea is to provide Earth-like living conditions while offering additional protection from micrometeorites and avoiding the rather unsettling sight of the opposite side of the ring overhead.Within the fictional setting, Meridian is constructed near Earth and eventually transported to the Jovian system, carrying an initial population of around 250,000 predominantly Earth-born settlers.

I've developed a procedural Python generator to create these habitats, including the cities, landscapes and exterior structures. I've also been 3D printing physical models of them.

This video is my first cinematic attempt to bring one of these worlds to life.

I'm trying to keep the wider setting reasonably grounded, with no FTL travel and genuine engineering and logistical limitations.

I'd genuinely appreciate your thoughts on the design, especially the structural challenges, shielding, artificial gravity and whether an enclosed rotating habitat of this scale makes sense.

It's very much an evolving project, and I'm interested in identifying where the engineering needs more thought!

I've been thinking about what it would actually take to make Mars habitable for humans.

We could imagine warming the planet, creating a thicker atmosphere, and eventually introducing ways to produce oxygen. But the technology, timescale, and resources required would be enormous, and we don't yet know whether full-scale terraforming is feasible.

I'm curious about the economics, too. Who would fund a project that might take centuries, and would there be any economic return, or would it mainly be a long-term investment in humanity's future?

Do you think terraforming Mars is realistically achievable, and what do you think would be the biggest economic obstacle?

Small note: This is my second account. I also help run r/spacefinance, a community discussing the economics, finance, and business side of the space industry.

This airship uses biomimetic propulsion, which includes jellyfish and fish modes.  Shock vibrations with extreme energy compensate for the small amplitude and this allows air to be used as a propellant more efficiently than a propeller. In this case, the vibrations create something like a vacuum tunnel and therefore the drag creates a load on the engine but does not impede movement in the usual sense. Theoretically this makes it possible to develop high speeds and enter very low orbits where air is still present.This is based on my and other experimental research, about which you can learn ore about on the simulator page. There you will also find a link to my GitHub where there are details.

This simulator is very minimalistic but it has complex physics of vortex propulsion and CFD shows actual airflow. I also recently added a solar sail function, but the forces are still poorly balanced and it is very dynamic, so if you get carried away, it is better to reload the page. I would be glad to hear any feedback if you try it:

https://www.masterogon.art/index.php/flying-saucer-simulator-2/

The deep cobalt in most popular images comes from contrast-stretching and color balancing meant to bring out cloud features. When researchers reprocessed the Voyager 2 data in 2024, they found Neptune is closer to a muted greenish-blue, much like Uranus, and only slightly bluer.

This is my attempt at what you’d actually see. It's a view from the upper atmosphere of neptune above its cloud tops, as if you teleported there and taken a photo with a phone. Sunlight there is about 1/900th as strong as on Earth, so the scene is dim, like dusk or heavy overcast day on Earth. Theres also a couple stars and Triton just above the horizon.

How I made it: The base was rendered in SpaceEngine. AI was used for the cloud texture, haze, realism, the moon, etc. I did the color grading and final adjustments in Photopea.

Analysis:

This image is consistent with what Neptune probably looks like, though nobody has seen it from this vantage, so it’s a plausible reconstruction and not a verified one. The clouds are long, thin horizontal streaks, as expected for a planet whose winds reach about 2000 km/h and stretch features along lines of latitude. The thick raised ribbons are meant to be high methane-ice cirrus. Voyager 2 showed long light-colored cirrus-type clouds floating high in the atmosphere, and NASA puts their heights at of the order of 50 kilometers above a deeper cloud deck, with streak widths of 50 to 200 kilometers. The lit left sides, the soft bluish shadows falling to the right, and the haze softening everything toward the horizon follow NASA’s description, in which the deck is deep enough that scattering by the overlying molecules diffuses light into the shadows, which look blue. The smooth haze-to-black gradient at the limb matches how any thin atmosphere looks edge-on, and the haze reaching above the cloud tops fits models in which a thin aerosol haze reaches high into the stratosphere. The color is a muted azure-blue rather than a deep ultramarine, which is deliberate, because Neptune’s true color is a greenish blue, and the saturated deep blue of the Voyager pictures came from enhancement. The lighting is dim because as I said, sunlight at Neptune is only about 1/900 as strong as at Earth. It also comes from one consistent direction which is shown by Triton’s lit left side, the faint cool brightening along the left horizon, and the cloud highlights and shadows. Triton is the brightest object in the frame, with a pale cream-pink tint and a smooth surface. That fits a moon with a surface reflectance of roughly 0.7 to 1, slightly pink nitrogen frost, and very few impact craters. At about 0.45° across, which is my estimate from its orbit, it’s roughly the Moon’s apparent size from Earth. The two stars are compact and dimmer than Triton, as they should be for an exposure set for a lit haze band.

Image 1 is meant to replicate a phone photo as if you teleported there and took a picture. It uses convincing lifted blue-tinted blacks, smooth blotchy noise left by noise reduction in the dark sky instead of film grain, restrained sharpening with slight local-contrast halos, held highlights, small glowing star points, a slight handheld tilt, and JPEG compression. It has no vignette or color fringing, because phone processing corrects both.

Like they are exactly like us (same blood, same bone structure, same organs, same bipedal shape, same limited eye color, same limited skin color, same evolutionary tract from ameoba to fish to primate to homo sapiens-except they evolved on different planets) but the only difference is that they have perfected genetic engineering (no diseases, no anomalies, no disorders, no boils, no pimples) and have different colored hair (blue, green, purple, pink, white). They even have our emotions. How would they feel about Earth in 2026? Could we be friends or foe? Could we have children with them? Could we immigrate to their planets

Suppose we get to a point where there is routine policing or active military engagements between ships or facilities. These actions are likely to occur within commonly utilized space lanes, transfer routes, or orbital points, and there is a great risk that such engagements will create large amounts of space debris, either through ship wreckage or kinetic munitions, which will create added risk to these locations, as that debris will orbit back to it's relative source point.

Space debris is one of the greatest threats to ships and space infrastructure, so ethical space combat needs to limit such debris and therefore require specific standards towards the weapons and methods that are used when engaging with opponents.

-Electronic warfare, firstly, would be an ideal first choice weapon to disable without destruction.

-Particle beams, could likewise disable and harm without destruction.

-Lasers will ablate surfacing and potentially eject troublesome material flakes as they aim to penetrate in order to disable or destroy a craft, but should generally generate minimal high energy debris, so could also be deemed quite ethical for space use.

-Kinetic rounds aim for material penetration or detonation upon impact. Collision debris, shrapnel or craft destruction is prevalent. Additionally, missed or fully penetrated rounds potentially retain their full energy and will eventually cycle back unless they have enough energy to break solar orbit. But, if a kinetic round could achieve a velocity great enough to break solar orbit (42.1km/s at 1 AU from the sun), it could be deemed reasonably ethical to use, assuming reasonable debris containment can be achieved after the conflict, otherwise they should likely only be used in remote areas of space.

-Conventional Missiles intentionally cause scattering destruction and may be one of the worst weapon systems to use in regards to ethical space combat. Unless the aim is for precision low impact disabling charges, and affixed to something more like a salvageable drone, they would be quite bad as a prevalent space weapon choice. As for being equipped with a Nuclear warhead, as a blast/radiation weapon that doesn't directly hit the target, they may actually be more ethical that most, since full vaporization of their delivery system would limit troublesome debris from being left behind.

-Shrapnel clouds either as a countermeasure, deterrent or defense would heavily disrupt the usability of an orbital plane and so would also be heavily restricted.

Feel free to share if there other likely weapons that may be deemed ethical or heavily restricted, or if you have views regarding how 'ethical' combat in space may be viewed

First of all, let me say that I simply love this channel. The content is great, examining future possibilities in depth and in a very scientifically grounded and even philosophically rigorous way and I thank the author for putting up such good content. But I have a few things to add and possibly object after watching "The economics of a post-scarcity universe" about some of the points that the video apparently argues.

1. There will always be scarcity of abstract objects of want.

Isaac Arthur ('IA" for short) says that some resources are inherently scarce, and I agree. Handmaid artifacts, attention, prestige and (human) energy will always be scarce, but at the same time, wants of prestige, attention and such needs can be modulated through psychological growth. Let's take love for example. Most people are striclty monogamous, and as such tend to think that love is a scarce resource and can only be destined to a single person at a time at best, but one could very well argue that it is perfectly possible to love more than one person with equal intensity. Of course, the physical energy and attention level required to fullfil the sexual and emotional responsabilities of other people is indeed scarce (unless your mind is uploaded and you can make several identical copies of yourself, which would make even physical energy and attention abundant, rather than scarce resource), but love is, arguably, not. And if people at large realized that, perhaps love would not be a scarce resource by default. The point here is not to argue that we should all be non-monogamous, but that whether an abstract object of want (like love, prestige ou social status) is actually scarce or abundant depends largely on societal norms and cultural expectations.

The pont is that the need for abstract objects of desires, like love, prestige or social status is far easier to negotiate with than the need for survival and they can, in principle, be made abundant by changes in societal expectations and cultural norms. It seems that one of the premises of the video is that, more or less, humans will be the just the same, and be greedy to some extent, but this is not necessarely true. People could, in principle, adjust their own mindsets to just accept that some things are either not possible or not worth having and be happy with that. Not everyone can be a world class physicist, or a high-skilled politician, or a astronaut, and that's ok. People can just be content with silently trying to do their best and just live the best life they see fit and material abundance will allow them to do so much more freely. I do think the desire for excellence is hardwired in human nature, but I don't think excellence is the same as achieving things like social prestige, love or power. People in a post-scarcity can acknowledge that power, responsability, prestige and love come as a result of the search for excellence, and do not define it and that matters for whether we think that such scarcity will always spark conflicts that have to be arbitrated by some form of money or currency. Which brings me to my next point.

1. Is money really inevitable?

IA seems to make the point that money (in some form), is inevitable, because resource allocation conflicts will always arise and therefore money does come as a objective and straightforward way to setlle such disputes. But I have doubts about that. I don't want to deny that resource allocation conflicts will arise even in a post-scarcity society, but will they be generalised and common enough in order to demand money (or something functionally equivalent) as an arbitrer? Sure, two (or more) people, can fight over a handmade painting by an artist they like, but will that be the norm in such a society and even more so to justify the need for money? And have such conflicts to be resolved through a money transaction? They could, in principle, be solved by arbitrage of the community they live in, AI, robots, personal molecular factories (like very advanced 3D printers), or simply giving everyone the means to find meaning in other things.

Post scarcity does not mean the absolute end of trade, and that I agree, but it does mean that the social division of labour which necessitates money, and its necessary state-sanctioned status (money isn't money if there is no social recognition of the currency enforced by a state), need not exist. Trade in such a society is just use-value trade. When we both have whatever material needs covered by economic production because of full automation and nearly infinite energy available, why would I trade with you for money? Money is a means to get things or services, not the things or services themselves. If the point of trade is to both parties directly enjoy things or services, or exchange favors or gifts, that is not a money transaction, at least, not one that seems reasonably like a money transaction. The problem is that IA's conception of money as just a convenient means to trade stuff, but money is not just that and even if it were, it does not mean that it is the only, or indeed, the most morally appealing option for trading and allocating resources that a post-scarcity society should sanction. And that brings me to my final point:

1. Resource allocation is necessary in a post-scarcity society but money is not

I do agree with IA that even a post-scarcity society must decide carefully where resources are allocated, after all, a post-scarcity society must not be wasteful. A post-scarcity society must manage wisely every atom of matter and every watt of energy it has at it's disposal, but resource allocation can be much fairer than today in such a society because people would no longer feel the need to hoard everything in fear that tomorow all may be gone because they trust that this society is wise, resilient and prepared enough for whatever the future holds, and I think that would have a positive impact on how just resource allocation is and how just it is perceived, which i think would have positive impact on social unrest and few people would feel society is treating them unfairly, hence greatly diminishing the need for an resource conflict management.

Long essay, but I hope that you guys have the patience. Thanks and I hope to see your thoughts.

The earth has a gravitational binding energy of 2.2*10E32 J of energy. What does that even mean?

To blow apart a planet with a short burst of a few seconds to a few minutes (depending the size of the planet), the weapon must be able to continiously output powers that are thousands to millions of times greater than the sun. Realistically speaking, they are probably going to be stationary constructs built around a black hole or the most massive stars, made of focusing arrays and energy storage banks spanning a dozen astronomical units. Instead of the planet exploding like in Star Wars, destroying a planet would be seen as a miniature supernova. In action, it would be something like this:

200 years in the past, a massive superweapon had fired towards where this unfortunate planet would have been today. Nobody on the planet could have seen the beam racing towards their planet at the speed of light, but when it struck, even the light of their home sun fades into background noise. In an instant, this planet became the brightest object in the galaxy. A wave of nuclear fusion reactions spreads from the point of origin, atoms in the air, water and ground splits and fuses again into various heavy elements. People living on the other side of the planet was fine for at least for a few seconds before the deadly moonlight reached them. At the power output of the planet killer, even the reflected light from their moon was more than enough to vaporise everything living on the surface and a few meters of crust. Life disappeared in the first few seconds, but the destruction continued. The expanding fireball violently pushed apart the crust, the mantle, and the core of the planet, to velocities greater than the escape velocity of the planet. When the energy beam of destruction fades away, only a glowing, expanding vapour cloud remains in the place where a thriving planet once were, slowly cooling down and pulled into an asteroid belt by the sun's gravity in the next few million years. And 200 years after the planet is destroyed, the confirmation reached the operators of that superweapon. The naked eye could just see a barely visible yellow star in the sky suddenly became the brightest star in the sky for a few minutes before dying down, the last breaths of a world that no longer exist.

If you want to move fast in a solar system, what methods are best?

Military enthusiasts will get hot under the collar upon hearing the possible methods: rockets, lasers, MORE lasers, and guns.

Or, more properly, chemical rockets, laser-pressure (the laser pushed the spacecraft), laser-thermal (the laser provides energy for the rocket), and pellet streams (pellets fired from fixed points propel spacecraft).

In part I, I analyse the different methods, and show that pellet stream propulsion is possible and the most efficient option. It also scales well to higher speeds (rockets being the one that scales the worst).

Laser-pressure, conversely, is by far the worst option, almost unimaginably bad at slow speeds. But it does actually scale best of all; when we move from interplanetary movement to interstellar movement, it could come into its own.

Hi guys was reading the Space Elevator Consortium's webpage on graphene materials for tether options. Made the above animation as a concept - any chemists here to check if it is realistic or not ?? Thanks! Ken
https://www.isec.org/space-elevator-tether-materials

Hey, was doing some worldbuilding and sort of realized something. If we had the technology for various things: lasers, EM guns, particle guns, etc, along with the guided missiles and chem guns of today, will they just cancel each other out without handwavium (mostly, sometimes the military still uses crossbows, it's just incredibly rare)?

For instance, is there no benefit to gunpowder and other chemical propellants over coil guns if you had the battery/power generation to make that viable? Would that same energy capacity make lasers blow them out of the water or vice versa? Would mini-missiles (which we already sort of have with some suicide drones) just make all of it redundant if there isn't some handwavium to deal with it? Etc.
P.s. Yes I know partial and plasma don't work in the atmosphere and the latter at all outside of incredibly close range. Either not including them or having some handwavium for that.

My ideal case is something like BattleTech or 40k where you have a variety of weapon types with different pros and cons, but if it stretches realism too much then I'd probably just drop that. Also doubles at satisfying curiosity in how future weapon tech would likely develop.

P.s. To avoid coming back here for everything like this (less you guys would like that, then sure), how do you tell these things without a week of crunching math and a few degrees worth of study? Just trying to avoid any sort of world building plot holes, tech or otherwise. Like with the Disney Star Wars hyperspace ram or 40k keeps using numbers for interstellar conflicts more similar to 20th century world wars.

Am I missing something here, because the way I'm looking at it, you could just live in one. Just make it via a matryoshka shell world with the most mass in the outer shell, some space to let in new matter falling in into the hollow center to be organized, and you are good.

The gravity on the inside wouldn't be as bad due to the same principle as the shell worlds, and you can even eventually be freed as the outer layer of the shell world erodes from the hawking radiation's negative half. Once it is gone, there wouldn't be enough mass for an event horizon.

Also, if you can make such structures out of active/passive supports, could you cheat escape velocity by simply climbing further from an object where the gravity is weaker? I feel like that probably isn't correct since I know he had talked about different densities of planets effecting the gravity on the surface but not the escape velocity IIRC, but if so, I don't know where I am going wrong.

P.s. Also, is there a point where you can't have a black hole or star or properly placed matryoshka shell world where, at that point, where you can't make it any bigger? Like, if a black hole got so big it just breaks the fabric of reality or something, or is there no limit there?

Hey! We've been working since last year on a In Control: Rocketry, a spaceflight sim where you build the rocket and wire up its control panel yourself. Sensors, inputs, outputs, the whole thing is Turing-complete, so however you want to solve a flight problem, there's a way to do it. It will be available on Steam in 2027.

Real orbital mechanics, a fictional solar system to explore, sandbox mode if you just want to mess around and blow things up!

Feel free to add the game to your wishlist if you want to support the project! See you in space.

The government or governments establish a public corporation, for example the Federal Reserve is such a corporation. Each citizen receives 1 share in that corporation, that share is non-transferable it pays a weekly dividend which is an equal share of its profits to every citizen. The corporations profits are tax deductible contributions from other corporation. Each corporation contributes 10% of its profits to this corporation and the government receives taxes on revenue for the remaining 90%. The public corporation then collects this revenue and after deducting expenses and then it writes a dividend check to every shareholder which is every citizen of every participating nation.