This article was first broadcast in Episode Seventy on 24th April 2019.
Lennon: I don’t understand why you’re against it.
Ostron: I’m not against it, I just don’t understand why you’re so in favor of it. I mean, what do you actually know about spelljammer?
Lennon: It’s D&D…IN SPAAACE
Ostron: Other than that.
Lennon: Um…it’s got spaceships.
Like many modern settings and elements of D&D, Spelljammer’s roots are in 2nd edition, and they owe their existence to a man named Jeff Grubb. As Keith Baker is to Eberron, Jeff Grubb is to Spelljammer, although he doesn’t have the laser focus on his setting Mr.Baker does. Grubb is the author of the first Manual of the Planes and created the forgotten Al-Qadim setting, and is credited as being part of the team that originated the Forgotten Realms itself. Later on, he was also contracted by Wizards to work on d20 Modern, their d20 Star Wars RPG, and Urban Arcana, as well as writing some of the lore novels for Magic The Gathering. Spelljammer specifically came out in 1989, and based on the forward in the book it was originally borne out of an animated discussion between Grubb and several colleagues after a convention.
Apparently, during the course of their discussions, the team decided something NASA has known for decades; space is hard. They wanted space to be fun, so they threw out a lot of conventional wisdom about it, starting with physics. After that they started throwing a lot more out. One of the Spelljammer source books features in-universe quotations on every other page or so that relate to the content being discussed. One of the quotes just says “In space, weirder is better”. It has no attribution to an in-game character, and I personally suspect it was the guiding principle the designers followed.
Getting into space in Spelljammer was comparatively easy. All that was required was a magic item called a “spelljammer helm” (that’s helm in the naval sense, not the piece of medieval armor). Practically, it was a chair with a special enchantment. If the helm was installed on a mobile object and a magic user sat in it, they could go to space. Now why didn’t everyone immediately die? Because any object that enters space automatically creates a bubble of air three times larger than itself. One human pulls enough air to last for 2-20 turns, while a 3 ton ship drags enough air to support three beings for 8 months. If it’s large enough, it also retains its original gravity, because magic. Other than the spelljammer helm, there were some other items and devices that allowed people to travel in space, such as the Gnomish Helm, which, and this is literally the description from the book: “…should not function. Their very construction seems to defy the nature of thaumaturgic law. They are impossible. Of course , being gnomish, they work anyway.”
Spelljammer’s universe is not what Neil DeGras Tyson, Stephen Hawking, or even George Lucas envision. In Spelljammer world, what we think of space is called wildspace. That space functions sort of like space as we know it, with stars and planets, but each pocket of wildspace is contained within crystal spheres or shells. Those spheres can be breached with magical portals created by spellcasters, or sometimes they just randomly happen. Also there are several creatures in space that can create breaches themselves. The spheres all sit in a substance called phlogiston (sometimes just called the Flow): a rainbow colored, highly flammable ether. Highly flammable means if you cast a fireball, it explodes immediately at three times the size and strength of a normal one. Lighting a candle will set you and everything within three feet on fire.
The irregularities also extended to planetary systems, and some would say are *most obvious* when discussing planetary systems. Spelljammer’s main book included rolling tables that usually kept things within the realm of normalcy, but every table had what we’re calling the “10% crazy.” The 10% crazy allowed things like planets carried on boats, a planetary system where some planets orbited clockwise and some counterclockwise, and planets with ring systems made of fire. Also, they didn’t even stick with 10% where planets were concerned. Half the time, planets would be normal spherical ones. But cubes, discs, triangles, irregular polygons, and planets with no defined shape were all within the realm of possibility and not even that unlikely. Also, sentient planets were totally a thing. The book did helpfully provide the planetary systems of major settings like Forgotten Realms and Greyhawk (which, incidentally, is a system where Oerth is the center of the system, and the sun Liga was demoted to the third orbital ring instead).
Theoretically any race can and did make it into spelljammer space, but the lore recognized two types. Major races had full spacefaring civilizations that made ships and established space outposts and colonies. Minor races were more just along for the ride or only sent a few ships into space at a time and weren’t really invested in it. Major races in original spelljammer were humans, mind flayers, beholders, dwarves, and elves. Minor races included the giff, gnomes (specifically Krynnish gnomes), halflings, centaurs, giants and kender
There were also the Neogi, a major spacefaring race of xenophobes that served as a sort of bogeyman race for adventuring in space, and the Arcane, a race that didn’t really have much celestial infrastructure but were credited with the creation of the spelljammer helms. Other races could be encountered, but for a variety of reasons most of them did not have a major spacefaring presence or interest. Initially there was only one type of dragon up there; called alternatively a radiant, celestial, or star dragon and they could be of any alignment. Several creatures unique to wildspace or the phlogiston were also created to act as random encounter-type antagonists. And, of course, Space Whales.
It’s also worth noting that, in the lore of 2nd edition, *Spelljammer* was the name of a particular ship that most spacefaring myths centered around. The ship itself was the largest spacefaring vessel (notable because it was too big to actually travel the stars based on most in-universe knowledge of how such things worked). Behind the screen, the ship is actually a race of semi-sentient beings and doesn’t require any crew, though it has a full settlement of about 5,000 beings on it. The exception is the captain, who is chosen by the Spelljammer itself and uses an “ultimate helm” when it wants to do anything related to the ship. Other than the captain, the creatures there don’t run the ship in the sense of controlling its direction, but they are beholden to the ship because it generates a persistent charm effect that convinces creatures to stay on and defend it. The creatures reproduce like rodents; hundreds of offspring are produced but very few make it to maturity because of the dangers of space, meaning there aren’t very many full-grown spelljammers, giving rise to the legend that all of them are the same ship.