Real Star Wars (Script) (Patreon)

Outer space, used and shared peacefully, offers incredible benefits, in communication, science, and soon resource gathering and even settlement. But there are some who eye the heavens with distinctly unpeaceful motives.

The decades directly following World War II were a time of optimism in many ways. Industrialization was finally improving quality of life for a lot of us, science was making incredible bounds, and our sights were set on the stars. It seemed to many that we were on a trajectory to a space-faring technological utopia. The United Federation of Planets was just around the corner. But the possibility of a much darker space age also loomed:  one in which the space around the Earth became highly militarized, and in fact massively weaponized.

In 1957, the Soviet Union launched Sputnik 1, the world’s first artificial satellite. They also tested the first intercontinental ballistic missile - ICBM. The space race had begun, and it inspired some incredible advances in science and exploration, culminating in the moon landing in 69. It also inspired a race to win the military advantage of low-earth orbit. By the early 60s, the United States and the USSR were regularly launching satellites of all types, and rapidly accumulating increasingly advanced ICBMs.

Those ICBMs were the first space weaponry. While they don’t actually enter orbit, they exceed the altitudes of most low-earth orbit satellites, hitting around 1200 km at the peak of their trajectories.  Despite definitely being in space, these are called suborbital trajectories because they don’t reach orbital velocity. “Ballistic” means that most of the journey is unpowered; ICBMs follow the parabolic path dictated by gravity when they’re between an initial boost phase and optional final guided phase. ICBM technology quickly developed to the point that a single missile could deliver multiple nuclear warheads several thousand kilometers away in a half hour. One Soviet program - the Fractional Orbital Bombardment System actually did enter true orbit, and it would allow multiple warheads to be delivered anywhere in the world from any direction.

As the arms race proceeded, both superpowers also turned to space to defend against this rising existential threat. Reconnaissance satellites – spysats –  in particular provided a level of intelligence-gathering previously impossible across the iron curtain. This was really the only effective way to monitor the rapid proliferation of launch facilities. Sure, those early spysats came long before digital cameras, and so film canisters were ejected by the satellites and retrieved either on the surface or in mid-parachute descent. The Soviets did build one spy satellite that contained actual spies. These were the Almaz space stations. Crews of 2-3 cosmonauts-slash-peeping-toms could develop film on board for rapid response to anything they spotted. Only two of these were actually crewed for brief periods between 74 and 77. The first Almaz station – Salyut 3 – was also the very first weaponized satellite. It was equipped with a 23mm autocannon, designed to defend against enemy anti-satellite measures. It was only ever fired once as a test.

But if we’re talking satellite weapons platforms, we should talk about Star Wars. By that I mean the Strategic Defense Initiative, announced by Ronald Reagan in 1983. It was an attempt to break the stalemate of the arms race and transcend the dubious security of mutually assured destruction by vastly increasing the United States’ missile defense capabilities. It included much-expanded surface-launch anti-ballistic missile – ABM – networks, but also, get this, an atomic-bomb powered X-ray laser satellite! This was the Excalibur program, and it very nearly saw the launch of what could only be described as a space-based super-weapon.

A quick review on lasers: they work by exciting electrons in some substance to high energy states. Then by passing electromagnetic radiation at a wavelength tuned to an energy level transition for that substance, “stimulated emission” can occur. The excited electron releases its energy as a photon that exactly matches the phase and direction of the seed photon. This produces a beam of “coherent” light, making it possible to deliver a very large intensity in a very narrow beam.

X-ray lasers were seen as extremely promising in missile defense because they can completely vaporize metal. X-rays are quickly absorbed in the atmosphere, but in the vacuum of space, these lasers can have ranges of many hundreds, even thousands of kilometers. Now normal lasers bounce the beam back and forth through the “gain medium” to build up power. But X-rays can’t be reflected easily, so a powerful X-ray laser needs to start with a powerful X-ray source. For Excalibur, that source was an atomic bomb set off behind an array of laser tubes. The satellite doesn’t survive the blast, but that’s okay. One blast is enough to power several dozen X-ray lasers, and each of those can take down an ICBM.  The dream of Excalibur was that a small number of platforms could take out the entire the Soviet missile fleet, even if it were launched simultaneously.

The media derisively nicknamed the strategic defense initiative Star Wars. It absorbed many hundreds of millions in funding from 1983 to 1990. Ultimately it was defunded for two reasons: One: it was never clear whether any of the 10 underground test detonations produced anything near the promised laser amplification. Two: no one could come up with a decent plan to protect the satellites. These things would need to live in Molniya orbits – highly elliptical orbits that allowed them to spend most of their time above a particular location on the surface – i.e. Russia. But that left them extremely susceptible to attack by missiles.

Another slight issue with the Excalibur program was that it would pretty thoroughly violate the Outer Space Treaty. This treaty, ratified by the US in 1967 prohibits signatories from placing nukes or any weapons of mass destruction in orbit or on a celestial body. The treaty is now ratified by 107 nations and seriously limits the potential for nuclear space war. ICBMs are still allowed because they don’t actually enter orbit, but the nuke-powered Excalibur was a definite no-no.

The Outer Space Treaty does have its loopholes. So-called “conventional” weapons are allowed in space. So non-nuke-powered lasers, and also the potentially very deadly kinetic impact weapons. The successor to Excalibur – Brilliant Pebbles – was just such a weapon. A kinetic weapon does all of its damage by hitting things with fast moving, non-explosive chunks of matter. Brilliant Pebbles proposed an orbiting weapons platform that delivered non-explosive missiles to destroy ICBMs. Besides not violating the Outer Space Treaty, this plan beat Excalibur because you didn’t have to destroy the satellite to use it. That meant a few “pebbles” could be launched to protect against an incoming anti-satellite missile while leaving the satellite functional. But even this proposal proved too expensive, and it was cancelled in the early 90s.

Another example of a kinetic impact proposal was Project Thor. It was never a funded project, as far as we know, but the idea was to drop 9-ton, 6-meter-long tungsten cylinders from orbit. They would strike the ground at Mach 10, with a destructive equivalent of more than 11 tons of TNT, similar to the lowest yield tactical nukes. These “rods from god” had a pretty niche application; very sudden precision strikes with no surface launch signature to serve as warning, and they wouldn’t violate the Outer Space Treaty.

By the way, both Excalibur and Brilliant Pebbles were considered as anti-satellite weapons – ASATs - as well as anti ICBM measures. But research into destroying satellites began much earlier. In the two years following the launch of Sputnik, the US was already testing anti-satellite missiles launched from a B-47 bomber. However the first successful ASAT missile was in 1985, when a US F-15 fighter launched a specialized missile that destroyed  Solwind, a retired solar observatory satellite.

The USSR pursued some very different ASAT paths. Their Istrebitel Sputnik – literally “satellite fighter” was a missile designed to actually enter orbit and maneuver up close to its target satellite before exploding. By the early 70s these things were successfully damaging test satellites. The program was even upgraded in the late 70s to be effective against the US Space Shuttle. True to their western stereotype as Bond supervillains, the USSR also played around with powerful ground-based lasers, which supposedly blinded some US spy satellites, and particle beams – actual death rays – which never really worked. Then there was the Polyus spacecraft; a full-fledged orbiting battlestation that would have had a megawatt laser designed to take out as-yet-unlaunched US anti-missile satellites. Polyus never became operational, though was very close.

Over the decades, multiple nations worked on adapting sub-orbital ballistic missiles to target satellites. However very few satellites have ever been attacked in this way. In 2007 China destroyed one of own weather satellites with a missile. This was scary in two ways. The resulting debris massively increased the amount of space junk in low-earth orbit; something like 1/6th of current tracked debris is from this one event. It also sparked a new race to develop ASAT capability. The US quickly followed in 2008 by destroying one of its own spysats with a repurposed ship-based antiballistic missile. The official line is that the satellite was decaying from orbit, and the purpose of its destruction was to avoid the unlikely event of its full tank of toxic hydrazine fuel from reaching the ground. Whether or not that was the true main motive, at the very least the debris wasn’t as dangerous as the Chinese explosion because that debris’ orbit will decay much more quickly.

Currently, the US, Russia, China, Israel and India have either functioning or developmental ASAT missile capabilities, and there’s a potential new arms race threatening. That’s concerning; even a few destroyed satellites could begin a chain reaction as the resulting debris hits and destroys more satellites in the increasingly crowded low-earth-orbit. There’s a serious risk of wreathing the Earth in a growing shell of mangled silicon and metal.

As real as that risk is, we once risked much worse; the Cold War arms race was on track to fill Earth’s orbit with satellite destroying weaponry and nuclear warheads. For the most part, and for the moment, saner heads have prevailed and humanity remains committed to the peaceful use of outer spacetime.