The “covert stars” collection is a series of booklets dedicated to the strategic and social aspects of space technology. This one, written by engineer and sociologist S.E Adewunmi, deals with an old point of contention: space stealth.

The first part of the book, “The Tale of the Hydrogen Steamer”, aims at dispelling the widespread historical myth that stealth is impossible in space. Adewunmi argues that, to become hard to find, all a ship has to do is to cool the hull down and thus nullify its infrared signature. The recipe for space stealth is a known quantity: it requires is a sleek ship, equipped with heat sinks, active cooling that keeps the hull near the temperature of the cosmic background and a deep black finish that prevents easy visual acquisition. Such vessels have been in use since the interplanetary age, almost two centuries ago; they are called “hydrogen steamers”, as they employ liquid hydrogen for cooling. Though not completely invisible, hydrogen steamers are nigh-impossible to detect at long ranges (> 50,000 km) and challenging to acquire at medium ranges (between 50,000 and 10,000 km), which makes them ideal space-to-space strike platforms. They can also be used in strategic deterrence, positioned in deep space at ideal strike times from inhabited planets.

In the second part of the book, “The Stealth Onion”, Adewunmi explores an enigma: if they are so good at stealth, why aren't hydrogen steamers more widely used in modern warfare? Indeed, though disposable stealth drones and probes are everywhere and widely employed in various roles, hydrogen steamers are few and far between, generally relegated to sublight operations in counter-insurgency contexts. As modern space to space warfare relies on fast, nimble vessels capable of tactical teleportation, the slow, cramped hydrogen steamers have little use in active combat beyond the initial volley: calculating tactical jumps requires them to deploy radiators to compensate for the heat output of navigation computers, nullifying their stealth capabilities. Though all superpowers maintain vestigial stealth fleets, their use is purely theoretical, and they have never been fielded in actual combat, neither are they employed as a strategic deterrent, where faster-than-light missiles occupy the same niche at a fraction of the cost. Likewise, “pirates” (Adewunmi considers this term antiquated and prefers the denomination of “unsanctioned militaries”) rarely have the means to maintain hydrogen steamers, as they require frequent refits to retain their stealth properties. And yet, orbital shipyards keep building stealth ships…why?

The question is addressed in the third part of the book, “Dark Lanes”. Adewunmi explains that the main use of stealth ships in the interstellar age is with…civilian outfits. Indeed, cargo ships have no need for fast translations or a large human crew: they can calculate their jumps over days or even weeks, negating the need for active heat dissipation, and operate on autopilot. Given that interplanetary and interstellar economic intelligence mostly relies on the analysis of ship signatures — a single engine wake gives a vector, a delta-v budget, a manufacturer, sometimes often an expected tonnage — stealth cargo ships, as light as they may be, create breathing room for cooperatives and communes to conduct unseen business, which might not necessarily be illegal in nature. Indeed, stealth cargo ships are primarily a tool of sovereignty, not contraband, which is much more adequately carried on regular cargo ships, where small packages are easily “drowned” among legal containers. Using hydrogen steamers to carry goods away from the prying eyes of interstellar superpowers can thus be understood as a political stance, a technical means to reassert the independence of non-aligned polities. In this regard, argues Adewunmi, the civilian usage of stealth ships as “dark laners” is not that different from their old military role in strategic deterrence: in both cases, stealth is a political statement.

Art by Sir_Lazz for Starmoth.