BDO of the Day: Helix

2025-11-11T00:00:00-05:00

Today’s (more like this year’s) Big Dumb Object (BDO) comes from Eric Brown’s two-book series Helix (2007, reissued in 2023) and Helix Wars (2012).

There’s a tiring amount of framing of the human side of Helix, in which a severely depopulated Earth sends out a lone ship of 4,000 sleeping colonists plus a skeleton crew of six. Eventually, the crew awaken to a crash landing on what they at first think is their target planet. Soon enough, the sun rises over something quite different, a helical planet that the author never quite describes to my satisfaction.

The Helix is a long, skinny megastructure wrapping eight times around a central star to form a single-stranded helix. It seems to be rotating around its cylindrical axis the way a topopolis can, but it also seems to be a solid planet, at least until book 2. The Helix contains approximately ten thousand worlds, divided by ten thousand seas, like a necklace of alternating green(ish) and blue beads.

There are no seasons, though the outer tiers are colder than the central ones. What happens physics-wise at the two ends of the structure is not addressed. The question of whether a solid ring or helix can rotate like a topopolis is moot because Helix Wars reveals that at least some world-beads rotate at different rates, so it must be jointed although no joints are ever shown.

The diameter of this tubular planet isn’t specified until well into book 2, nor is the length of the individual world-beads. The seas are described as a thousand miles wide, i.e., long. Though they seem to serve as buffers between the different atmospheres and geographies of the individual worlds, how this works is also never described. Most of the travel in the books is by spaceship, at an unspecified speed. So in book 1, the biggest clue to the dimension of the world is a statement that “there’s sufficient landmass in the entire helix to contain oven ten thousand planets the size of Earth.” The distance between the tiers (later called circuits) of the Helix is never discussed.

In Helix Wars, a tale of interworld conflict, a few humans get to see the “spine” of the Helix, a tunnel two hundred kilometers (125 miles) in diameter running the length of the Helix, within a wall ten kilometers thick. There’s some unnecessary artificial hollow-earth-style gravity to counteract the shell theorem. The tunnel isn’t really necessary for either the plot or the structure, though gigantic machines within it are somehow supposed to be maintaining everything from a distance of “almost 8,000 kilometers” (4971 miles) from the surface. In addition to this radius, a length for the Helix is also finally provided: 200,000,000 kilometers (124,275,000 miles). These are big numbers, but they’re not big enough; see the calculations below for details.

Both novels provide entertaining adventures involving a reasonable number of worlds and species of the Helix; they’re very much a typical example of the genre rather than one of those novels that provide only a glimpse of the BDO in the last chapter. The lack of physical detail about the Helix in the first novel interfered with my sense of wonder, as did the reliance on magic technology once details were revealed (e.g., the unnecessary artificial gravity in the unnecessary tunnel through the center of the Helix), though my personal BDO construction principles probably don’t matter to the average reader.

Helix
Helix Wars

Spoilers

Helix starts out slowly, with a remnant of post-ecopocalyptic humans living a hardscrabble life on Earth. Enough government survives to send out a colony ship to a nice-looking sun a thousand light years away, and enough ecoterrorists survive to necessitate secrecy. It’s never clear whether terrorism or accident causes the ship to crash in their target system, but it is eventually explained that the Builders of the Helix concealed it from Earth’s view. If you’re likely to be annoyed by all the eco, this may not be the novel for you; I thought it worked well enough in the context of a BDO story. The human characters are serviceable, if not particularly memorable.

The main alien characters are a bit more interesting. A race of otter-like humanoids living on a cold, cloud-shrouded world-bead have developed an unnecessarily insular religion in which the universe is a sea of gray with their city in the middle and not much else. There’s as much bickering about religion in their chapters as there is eco-handwringing among the humans. If you’re likely to be annoyed by all the atheism, this may not be the novel for you; I thought it came close to working well enough in the context of a BDO story but the situation felt more assumed than explained.

Eventually some otters stumble across the spaceship of a lone representative of a third alien species, sent to recover technology stolen by the religious fanatic otters. In the process they rescue the humans and escape to another world, Phandra, inhabited by a species of peaceful, apparently primitive but psychic aliens who have been waiting for their arrival. They show the humans and otters (the lone alien doesn’t make it) to a crashed ship of one of the engineers that manage the Helix. In this way they discover where the world of the Builders of the Helix is, fly to a world neighboring it, and use native transportation (living flying carpets) to reach the Builders' world undetected by the pursuing religious otters.

In the best of BDO fiction fashion, they meet the Builders (after a fashion), discover the purpose behind the Helix, and settle down for the long haul. Oddly, the two impossibly estranged otters get back together.

Helix Wars gets going faster, with more adventure and fewer Big Issues. Humans have had two hundred years to settle into their new colony and new interworld peacekeeping role. As is all-too-common in science fiction, all their futuristic technology disappears when it comes time to give a character a tragic backstory involving the death of a child, but otherwise the humans are doing well on the Helix…until an upstart alien world (Sporell) invades its next-bead neighbors (which happens to be Phandra, from book 1).

Sporelli shoot down a human shuttle that flies by at the wrong time, and only the pilot, Jeff, survives. Humanity’s bureaucracy doesn’t seem up to the task of rescuing him, never mind actually fulfilling their peacekeeping duties, but coincidentally he has an alien friend Kranda from the engineering race (the Mahkan) who owes him a favor debt of honor and goes after him. Before she can rescue him, the locals, Phandrans from book 1, find him, treat his injuries, and try to get him home. They fail, but the Mahkan succeeds, and there’s a brief interlude on New Earth before Jeff and Kranda reunite to rescue some captive Phandrans now being held at the next world and target along the line, D'rayni.

They are only partly successful in this mission, and a setback sends them fleeing to the tunnel at the center of the Helix. They travel by its advanced magic car system to Sporell itself, where we get a dose of this novel’s Big Issue, fascism bad, but is it bad enough to justify killing Hitler? This particular cloud-covered world is extremely gray and fascist, and its dying Supreme Leader is planning a surprise to extend his domains and his life indefinitely.

While the surprise is a neat plot twist, the vast scope of the Supreme Leader’s ambitions makes his minor incursions on the surface of the Helix, heretofore a large part of the plot, feel irrelevant. Our lone heroes handle the new threat with aplomb, magic builder technology, and too much arguing about killing Hitler. Only off-screen do the peacekeepers finally get off their collective butts and restore the peace on Helix.

There’s another meeting with the Builders, and a denouement that would have had more impact with more believable relationships. (The two impossibly estranged humans get back together.)

Calculations

The radius of the Helix (at an access mountain on the D'rayni world) is almost 8,000 kilometers, or 4971 miles, more than the radius of the Earth (3,963 miles). The length of the Helix is 200,000,000 kilometers (124,275,000 miles), so about 20,000 kilometers (12,428 miles) per world. Minus the thousand miles of ocean, this is about 11,427 miles per world. Each world would have a surface area of 2π times the radius times its length, or 356,900,000 square miles. This is closer to twice the size of the Earth, so the Helix is about the size of 18,000 Earths, not 10,000 Earths. This, however, is not the major error in the BDO.

Without knowing the distance between the tiers, we can only approximate the distance of the Helix from its central sun. Judging from the only slightly uninhabitable ends, the cover art, and the ziggurat transport system that the characters use on one occasion in book 1, the pitch of the helix is minimal, with a distance between tiers of perhaps as little as ten times the diameter of the beads. For a guess let’s call it 100,000 miles.

With that and the length of the Helix we can approximate the radius of the Helix—the distance between it and its central sun—at 2,500,000 miles. Unfortunately, this is not a reasonable distance from a G-class sun, being about one thirty-seventh of an astronomical unit (92,955,807 miles). Tweaking the distance between tiers is no help; the Helix’s goose is cooked. In other words, the Helix is an object lesson on not pulling numbers out of your arse.

An 8-tiered helix fitting the parameters of the book but positioned a habitable 1 AU away from its sun should be 4,672,468,555 miles long, with room for 376,000 worlds, not a mere 10,000. Another option would be to place the original Helix in orbit around (but outside of) the sun rather than being a spring with the sun at its center. But such a helix would have seasons, and the temperature would vary across the diameter of it, unlike the weather of the novels.