Rockets, the Long Arm of History, and the Future of Space Access

As the CEO of a company building a non-rocket system for putting stuff into space, a question I always jam down people’s gullets (for didactic purposes) is ‘Why go to space with rockets?’ The short answer is we use rockets because they are the right technology for putting atomic bombs onto the Earth, not because they are particularly good at getting mass to orbit.

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During WW1, the Germans built a super-gun capable of pushing ~100 kg over 120 km distance. Despite its impressive capability, the Paris Gun was a poor weapon. It could only move via rail and the heat generated during firing burnt the barrel out after sixty shots. Yet, warts and all, it got people's attention. Particularly Parisian people. So much so that after the war one of the conditions imposed on Germany was Allied control of artillery production and developments in artillery technology.

With their artillery development no longer secure, the interwar German military invested in alternative ways of pushing payloads long distances. As a result, by WW2, they were a decade ahead in rocketry. A fact on display in the havoc wreaked by the V-2 weapon system in the latter half of the war. The V-2 was scary because it flew too high and came down too fast to be intercepted. It was the primordial big-liquid-fueled rocket and the direct precursor of everything that has come since—Soyuz, Saturn 5, Falcon 9, and all humanities ICBMs.

It is hard to overemphasize the importance of captured V-2s, and Germans, to the later success of both Soviet and American rocket programs. In the course of WW2, Germany launched over 3000 V-2s at London and other Allied targets. They learned a lot doing it.

Not that those launches were decisive. The V-2 was only a little better than a long-range bomber while being a lot more expensive. Most allied thinking after victory in Europe was that the Nazis had squandered their resources on the V-2 when they should have been manufacturing blankets and bullets. But then, Hiroshima and Nagasaki were wiped off the map. It was immediately obvious to world leaders that an unstoppable delivery system mated to a city-leveling warhead would define the post-war world.

A rush of investment into rocketry followed. The U.S. and USSR kidnapped hundreds of German engineers and dumped hundreds of billions of dollars into rocket development. The Space Race of the 1960s-70s allowed the belligerents of the new arms race to show their respective mastery of the Sword of Damocles without blowing up Pacific islands.

Yet despite the money and many decades invested, orbital rocketry remains a marginal technology. If a rocket can deliver 1.5% of its wet mass to orbit, it’s a damn fine rocket. If it blows up *only once* every 100 times it flies, that’s considered pretty good. Can you imagine these standards applied to other vehicles? Your car would be the size of a house, cost a hundred million dollars, and would kill you monthly.

Orbital rockets demand huge development efforts, large complex infrastructure, and are expensive to operate all because the underlying physics barely allows them to function. If Earth's gravity were a few percent higher, or the atmosphere a little thicker, chemical rockets simply wouldn't be able to put anything into orbit.

But as part of nuclear weapons infrastructure, a marginal, expensive, technology is acceptable, and in some ways, preferable. You don’t want just anyone to be able to build them. And who cares if they are more expensive per unit? If you launch a nuclear salvo once, you don’t really need to worry about the cost of the second. They don’t even need to be that reliable because their role is deterrence. The *possibility* of a nuclear-tipped rocket working is so terrible that it’s 99.9% of the value.

It is a happy accident of our physical circumstances that rocketry is capable of pushing mass to orbit at all. However, if rockets couldn't reach orbit, the Earth would still be bristling with them. The use cases for cruise missiles, ICBMs, missile artillery systems, and RPGs get no weaker if earth's gravity is ~3% higher. Suborbital is a lot easier than orbital, and it is involved in 99% of the defense cases.

Over the past 100 years, the huge amount of defense cash and engineering effort spent weaponizing rockets has distorted what people think the possibilities are for space launch. It’s hard to discount that much precedent, but fundamentally we are trying to solve a problem with a tool built with a very distinct application in mind. We have to be careful not to let the weight of so much historical and technical momentum blind us.

In the 1960s a Canadian ballistics engineer, Dr. Gerald Bull, built a super gun that put ~400 kgs up to 180 km altitude for the US Army. Bull was obsessed with the idea of shooting satellites into space. The project was called HARP; the total budget was ~$8M, the gun cost was on the order of $5000 to shoot, and the project took 5 years from start to finish. While the g-forces on the payload were two orders of magnitude higher than in a comparable sounding rocket, the cost per kilogram to altitude was four orders of magnitude lower.

HARP was ultimately transferred to the control of the U.S. Air Force. There was no commercial satellite market at that time, so Dr. Bull was fully dependent on DoD for funding. The Air Force recognized the advantages of Bull’s system but also saw the same military disadvantages of the Paris Gun. It was huge and stationary, which, in the hide-and-seek ambiguity of nuclear deterrence, made it a poor weapon system. Also, the recurring cost advantages were immaterial. What’s the point of low marginal costs if you end civilization with the first shot? Fundamentally, missile command was in the Brezhnev scaring business, not the low-cost space access business. HARP was shuttered in 1966.

Rockets themselves have been the victim of this same dynamic. The Saturn 5 still holds the record for the most mass-efficient orbital rocket ever built, but it was too big and too expensive to attract defense customers. They could make do with smaller, less efficient rockets. Once the Americans ‘won’ the space race with the USSR, NASA no longer had an existential/defense justification and had to move to a congressional-pork model to survive. The high watermark of human space access (as of this writing) was arguably when the last of the Saturn rockets flew in 1973. It’s been downhill since then.

Today, SpaceX’s Starship is poised to remedy that and bring big rockets back into the world. It is no coincidence that Starship, by big rocket standards, has also received almost no development dollars from the DoD. While the DoD has started to wake up to the defense advantages of low-cost high-cadence space access, that ship turns very slowly. Fortunately, SpaceX and other modern launch providers have an advantage that the Saturn rockets and HARP didn’t—commercial demand for space access. This lets providers build rockets optimized for *the* critical metric: dollars-per-kilogram to orbit.

Back in 2010, people thought the Falcon 9 was idiotic because it, and the people who were building it, didn't look old and boring enough. Some of the same humans (fewer now) think Starship is silly for much the same reason. Despite these criticisms, in an objective sense, Falcon 9 and Starship contain almost no new technology. These rockets instantiate ideas engineers from the ‘30s worked on. There is nothing about the Falcon 9 or Starship that would have prevented them from being built in the 1970s. In some ways, they may have been easier to build then.

These rockets are awesome, not because they are new technologically, but because they were designed with space, for space's sake, in mind. For every other major rocket system, catering to defense needs was the primary design driver, and space was a side hustle. The revolutionary ideas embodied in the Falcon 9 and Starship are economic, not technical, with their emphasis on reusability being an obvious example. SpaceX is actually a very technically conservative company. They seem daring only because of the comparison to the defense primes (who would build billion-dollar products out of mud and elk bone running FORTRAN if they could get away with it). Also, when you are building a business on technology as marginal as rockets, technically conservative is the right way to be. At several points in its early life, SpaceX was one exploded rocket away from failure. This dynamic of high costs and resultant technical conservatism is a trap history has imposed on us.

Humans emigrating to space will need tens, to hundreds, of tons of material per person. Food, fuel, habitat, water, raw building materials, tools, etc. It will take many decades and lots of investment for off-world settlements to be, even partially, self-sufficient. To start that process, humanity needs access to orbit to cost ~$10/kg or less. As cool as Starship is (and it is very cool), in order for it to reach that price point, tens of thousands will need to be launched each year. To put that into perspective ~100 Starships could lift everything humanity has collectively put into space over the past 70 years. Finding the customers to drive those economies of scale may be impossible given that rockets are just fundamentally expensive. Further, if it is possible, it will take decades. Probably lots of them. That’s just not good enough for me.

SpaceX has been as successful by looking at rockets and saying, ‘If this was built with low-cost space as the goal, what would it look like?’ Longshot is trying to do the same thing while stepping further back, and asking the question about launch more fundamentally.

Space launch thinking has been defined by more than a century of customers demanding rocket-based weapons platforms that produced space access as a by-product. If the goal is to get mass to orbit cheaper, then the future does not look like ΔV = VE * ln(ML / ME). That log function is simply too punishing, and dropping the cost of upmass is too critical. Trying to imagine a coherent future where millions of humans live and work in space, where rockets are the only tool for launch, is either an exercise in magical thinking or very depressing.

We have to try approaches with fundamentally different physics if we want fundamentally different economics. To do that, we need to look hard at the technical trade space and ask ourselves, ‘What does launch look like when it doesn't need to kill people?’ We don’t need to stray into science fiction to find answers.

History got us into this mess and history can get us out.