Story Idea: Oort Cloud Civilizations

The following article was written by John H. Reiher Jr.

I’ve written a short flash fiction about humans who live out in the Oort cloud, far from the warming rays of good ol’ Sol. It was published on 365 Tomorrows, and it was called “Between the Stars”.

The premise was that of a spacefaring civilization that lived between the stars, hopping from one frozen ball to another frozen ball, mining water, minerals, and metals from those bodies they were given permission to mine. I came up with an extensive background for this idea, and I thought I’d share it.

The Background:

Oort cloudThere is no FTL travel. Not even a little bit. If you want to go to another star, you can brute force it with a massive generation ship, or, like the Oort cloud civilization, slowly, moving from body to body, controlling their populations, and building new ships from the material they find out in the edges of a star system.

Their vessels are massive, yet light. They have to be as they use solar sails. Not the dinky 1km or 5km solar sails used in the inner solar system, these are massive 1,000km and bigger sails. They have to be that large to catch the dim light of the sun and the frail solar wind. When not traveling, the sails are reconfigured to illuminate the vessel and it’s occupants.

When traveling, only a handful of crew are awake to take care of the vessel, the rest are either in suspended animation or stored away as embryos. Some of the crew are technically millennia old, having been conceived thousands of years ago, and only recently “decanted” and brought to term.

The Civilization:

The Oort cloud civilizations are very old; they have been in space for tens of thousands of years. They have stories about how they originally came from the inner worlds, but no one really believes that. Those worlds have a massive gravity field, and would crush an “Oorter”. Their stories and history are all about clan interactions and stories about the family. Some individuals stand out in the family story, but only as an example of how the family works together and seeks a solution to problems.

Over the millennia, the Oort cloud civilization has divided into “families” and “clans”. Each family controls a single vessel, and is beholden to the head of the clan. The clan consists of a number of vessels under the control of the head family of the clan. The head family of the clan controls all information that is sent to each family. Information about how to make another ship for instance. Or how to use carbon instead of iron or other metals to build a ship. Each information packet contains a self-destruct code to prevent the family from using it more than the agreed upon number of times.

Of course, the truth is that the information is in the family’s computer already and all the “Information Packets” are a collection of one-time keys to unlock and use that information. If a family ever figures this out, they could be free of the tyranny of the main clan family. This is how new clans are formed.

Oort cloud sail shipThe Oort cloud vessels are wonders of automation and design. All are controlled by semi-sentient computers that control every aspect of the ship, from life support to the tension of the atoms thick solar sail. The semi-AI has a personality for ease of use and control. There is no danger of it going all HAL 3000 on the crew. You can hold a conversation with it, but it’s more like a very good LISA program, than an actual person.

The sails themselves are made up of a single sheet of graphene, coated with two or three layers of metal. Any metal. This makes for a colorful looking sail, with copper hues mixing in with iron and titanium, even some cobalt blues. The sheets are stretched between carbon nanotube struts no thicker than a pencil, but capable of collapsing accordion like when necessary.

There is trade between families and clans: New stories, new ways of doing things, and most importantly, new genetic material: Originally, there were 100 vessels that had been built to go out into the Kuiper belt, and eventually the Oort cloud. Some decided to head for the Alpha Centauri system, some are just working their way to the heliopause, where the solar wind meets the galactic wind. What they will do when they get there, they aren’t quite sure.

These 100 vessels, plus a few more that followed, consist of the sum total of human genetic material available for use. Thousands upon thousands of embryos were stored aboard these vessels and over the millennia this resource has been completely used up. So, to prevent too much genetic drift, ships will trade genetic information. Space is vast, the only time two ships are close enough to transfer personnel and physical goods between them is when a family builds a new “child” vessel on contract for the head clan family.

The new genetic information is sequenced from a unique subject and then transmitted to another ship in exchange for unique genetic information from them. Then a donor ovum cell is prepared and the chromosomes of both the cellular DNA and mitochondrial DNA are reversed sequenced into actual chromosomes and implanted into the ovum. Then the ovum is implanted into a crèche mother and the child is brought to term.

Some of these unique genetic sequences have been traded almost completely around the solar system, one ship at a time.

Humanity has changed during the millennia. Now called the “Hmon” they have adapted to living in space. This occurred naturally and by genetic engineering. Every Hmon has hand-feet that consist of three toes, two forward, and one to the rear. Bones are mostly cartilage with only the jawbones, teeth and the skull being made of solid bone. The inner ear has been changed to deal with free fall and three-dimensional movement. Hmon are much more agile than humans, but genetically, they are only 0.1% different from humans. Cross breeding between the two could still be done.

If it is not obvious, the Hmon have a long view mindset. They are the masters of planning out projects that will take generations to complete. There is no hurry out near the edge of the solar system, every thing moves at a galactic pace. The Hmon that are aiming for Proxima Centauri plan to reach it in 3 to 5 thousand years. They are the ultimate nomads, never setting down any roots, just moving from one icy ball to another.

Possible Story Ideas:

A Life Among the Stars

This story follows an individual from birth, childhood, young adult, middle age, and his or her later years. It’s a story of how this person grows up to be the person who leads their family out from under the control of their parent clan family to become their own, independent clan, in control of their own destiny.

Highlights would include this person learning how to work with and eventually control the ship’s semi-AI; meeting and wooing the love of their life; siring their old family and watching their children grow; figuring out how to bypass the lockouts on the information in the ship’s databases, freeing the ship; the retaliation from the head family when they find out that they have lost control in the form of “deadman” codes that threaten to shut down the semi-AI and kill the crew on board. It would climax at the last minute with the protagonist remembering something from childhood and undoing the deadman lockouts.

A Person Out of the Past:

A family is mining an Oort body for necessary minerals to build a new ship. One of the mining units finds a massive amount of metal. Only… it’s in the form of an unknown type of space vessel. The vessel has been there for millennia, its hull breached in several places. Inside are the desiccated corpses of the crew – a human crew. However, beyond hope, there is a survivor.

This human ship used a variant cryopod: It didn’t freeze people, instead with a unique cocktail of chemicals and enzymes, it freeze-dried the person. In this form, they would last forever until reconstituted. The cryopod is intact and only requires some minor repairs to restore it to full function.

The occupant is revived, but, instead of the world they were supposed to wake up on, they find themselves among the odd Hmon, a stranger in a strange land, unable to speak to the Hmon directly. The semi-AI, however, can talk to them, as they are using the original language of the first ships. So communication between the human and the Hmon is possible.

But the story is not from the POV of the human, it’s from the POV of the Hmon and how they deal with this genetic throwback from their past. The human is definitely a fish out of water. At first, hideously strong and quite capable of punching a hole through the thin material of the ships hull, the human eventually loses muscle mass, bone mass and becomes ill from prolonged microgravity exposure.

At first, the human refuses to be “fixed” by direct genetic manipulation, but after one or two close calls, they agree to be modified. It doesn’t happen overnight, or in this case, over sleep cycle, but bit by bit the human is transformed into a Hmon.

And the Hmon want to keep this person alive because this person knows stuff, like how to access the ancient databases on board the damaged ship – ancient history that has been long lost or hidden will now be available to the people of this Oort ship. They now have power, but do they know how to wield it?

This article was written by John H. Reiher Jr.

You can read John’s flash fiction story, on which this article was based, at You can also read John’s personal blog here.

  • Great article John. Thanks for sharing.

    This ties in pretty well with one of my own story ideas – “Valnia”. Maybe Valnia could be a Hmon.

  • John Henry Reiher, Jr

    Interesting, she could have been a “Hmon”. Well, I hope folks like this idea!

  • Paulo R. Mendes

    This is a interesting setting – it remembers me of Orion’s Arm universe.