TL;DR
The chyrons on cable news and everyone’s x feeds were wall to wall this past week as House intelligence committee chairman Mike Turner (R-Ohio) went public with reports of a non-specific but massive national security threat that he was asking the Biden administration to make public so that the threat could be more effectively addressed:
Within hours we got a slightly less cryptic disclosure that this was almost certainly originating with the Russians and a potential nuclear threat in space. At this point the rumor mill went nuts: there was all sorts of speculation about everything from nuclear weapons in space to a nuke designed to pollute low earth orbit with radiation that would kill Starlink to nuclear powered jammer satellites that were going to take down GPS.
While it’s no secret that the Russians (and the Chinese for that matter) have been interested in attacking our space assets for quite a while - the first Chinese ASAT test in 2007 led me to do work on countermeasures that led to some of my earliest patents while I was a junior engineer at Raytheon - I think it was really the combination of nuclear and space here that has captured the public attention on a matter that many of us in the space community have been preparing for and fretting about for 20 years or more, generally away from the public eye.
Nuclear in space is not a new thing at all: we (the United States), the Russians and others have literally flown dozens of missions with nuclear materials (including actual nuclear reactors) on both deep space probes and actual satellites. In the 50s and 60s, we even conducted nuclear tests in space, perhaps most famously in the STARFISH PRIME tests in 1962, which led to a lot of the early work in EMP when a lot of electronic infrastructure in Hawaii and the pacific was damaged by the fallout as the fireball and ensuing charge pulse interacted with the Van Allen Belts in the earth’s ionosphere (You can see a picture of this in Figure 1).
What follows is a general overview of the history of nuclear power, nuclear weapons and nuclear propulsion in space, along with some speculation about what the Russians might have up there based on what limited facts are available (nota bene: I haven’t seen the classified materials related to this class of threat, so I have latitude to speculate based on first principals and past behavior - all this is based on open sources or derived from them).
Outer Space Treaty
I know what a lot of you are thinking: “hey wait, don’t we have a treaty prohibiting nuclear weapons in space?” And you would be right! In 1967 the US, USSR and about 114 other government signed the Outer Space Treaty banning the fielding of nuclear weapons in space, stating that states shall be liable from damage from their space objects, and that states should avoid the contamination of space and other heavenly bodies. Russia, as the successor of the USSR is technically subject to this treaty.
But as we’ve seen in recent years they have been pulling out of treaties or outright violating them left and right since about 2014 when they invaded Crimea. The most notable (and nuclear) one is the Intermediate Nuclear Forces treaty, which banned the ground deployment of missiles with a range between 500 and 5000 kilometers, which Trump pulled us out of in 2019 due to the Russians supposedly deploying their own intermediate range missiles. One (Ukrainian) source actually put the number of total international treaties they are in violation of as high as 400 - how nekulturny!
But treaties are only as good as either the goodwill of their signatories to comply or the counterparties to enforce. So unless the US is willing to go full Walter Sobchek and start flashing a piece on the lanes to enforce the rules (See Big Lebowski clip below), it’s likely the Russians will just see this treaty as yet another “suggestion” they can violate at their convenience (this may in fact be where Mike Turner was going with this):
History of nuclear weapons in space
The United States actually conducted the highest altitude testing of nuclear weapons in Space under Operation Fishbowl in the early 1960s over the South pacific, with the infamous Starfish Prime test, a 1.4 megaton explosion at 477 km - low earth orbit. This was a follow on to earlier tests that took place in the Atlantic under Operation Argus in the late 1950s. Here’s some video footage of that test you can watch, with the explosions forming perfect spheres at first and then the plasma begins to distort with interaction with the earth’s magnetic field (the so-called Van Allen belts)
If you are interested in the scientific testing regime that goes into characterizing an explosion like this (or just enjoy listening to science narrated in a perfect Transatlantic dialect), here’s a similar length video on the preparation for the Starfish prime test:
At the time, the US was experimenting with the idea of launching a nuclear weapon in the path of incoming Soviet ICBMs to try and neutralize them through radiation exposure, a phenomena known as the Christofilos effect. This is when a wall of Bremsstrahlung radiation caused by the enormous electron flux generated in a nuclear explosion is slowed down by interacting with the earth’s magnetic field - this causes a huge radiation cloud that would potentially damage or degrade any incoming missile. More on this later as we talk about why lighting off a nuke in orbit is a very bad idea.
The idea of nuclear weapons as a defensive weapon was also not a novel concept limited solely to the space domain: the AIR-2 Genie was a nuclear cruise missile designed to be launched in the path of a wing of incoming Soviet supersonic bombers (sidenote: my great uncle Robert Mintz, Z’’L, was almost unwittingly the weapons systems operator in an F-106 for a AIR-2 nuclear test over the gulf of Mexico while working at Hughes Aircraft in the early 1960s). Similar lunacy was prevalent throughout the DoD during the pre-precision strike weapons era. It’s therefore no surprise that they thought that launching nukes into space in the path of ICBMs was an idea worth experimenting with.
The Soviets wouldn’t leave it to the Americans to have all the fun and conducted their own high altitude nuclear tests, during the height of the Cuban Missile Crisis in 1962, under the codename Project K. Little video footage is publicly available from these tests. The EMP effects of these tests were well characterized (and much more impactful to civilians on the ground), as the Soviet Union had the disadvantage of not having the Marshall Islands to do nuclear tests out over the uninhabited pacific, so they simply did them overland, usually Kazakhstan (which somewhat explains Borat). The highest altitude explosion (Joe 105) at 300 km actually disabled a powerplant in Karaganda, Kazakstan and measured a 2500 amp current across very long buried powerlines for the experiment- yikes! High altitude EMP is a very gnarly thing.
Why is on orbit EMP so bad? What about radiation?
A tremendous amount of research has been conducted on the impact of high altitude EMP and it remains one of the doomsday scenarios that could literally bring an industrialized country to it’s knees. A high altitude EMP event could literally disable or disrupt all electronics in a given area for 100s, if not thousands of miles in an instant. If you look at our “just in time” supply chains, along with our dependencies upon things like refrigerated food distribution and storage in urban areas, electronic payment systems, and even electronics in our cars and delivery trucks, it’s not hard to imagine a scenario whereby if a large percentage of electronics currently in use were taken off line were disrupted or damaged, civilization as we know it in many urban areas would cease to exist in 7-14 days. Better have gold, ammunition and scotch!
In all seriousness, this is a scenario that has been exhaustively studied by the Pentagon and one for which many military systems today have been assigned hardening requirements, known as High Altitude EMP or HEMP requirements for decades. What’s particularly interesting about these HEMP effects is that due to the unique structure of the earth’s magnetic field, they can actually be decomposed into three waveforms: labelled E1, E2 and E3. E1 is an extremely intense but very short pulse width, E2 is a longer but less intense pulse and E3 lingers for minutes and is really two waveforms in one. You can see a graph representing these effects in Figure 2.
Breaking down the potential failure mechanisms of these effects: E1 is the closest to artificial EMP generated by High Power Microwave (like what you see in counter-drone and tactical counter-electronics systems) and is a broadband signal that interacts with antennas and short metal traces. E2 is similar to a nearby lightning strike and can be mostly mitigated through a competent grounding schema (otherwise known a “star ground” layout) or Faraday cages if you are really ambitious. E3 tends to have more impact on long cables and power lines and can result in very high currents accumulating similar to what the Russians saw in the Project K tests mentioned above.
Most modern electronics are not very hardened however and certainly not against nuclear weapons blasts at high altitude. As you can see from Figure 3 below, it’s likely that very high field levels would propagate for hundreds, if not thousands of kilometers if a single 1 megaton nuclear weapon were to detonate on orbit.
It’s clear from this that the impact of high altitude EMP from a LEO altitude (300-1000 km) alone would create some really nasty EMP impacts on the ground and on-orbit - and that’s before we even begin to talk about the radiation effects caused by the Christofilos effect mentioned above.
A lot of work has been done on the radiation effects from detonating a nuclear weapon in space and the general consensus is: don’t. However, the Starfish prime explosion in the 60s actually shortened the life of over 1/3 of all on-orbit satellites at the time. Modern satellites have much more robust radiation hardening than those built in the 60s thanks to decades of research and work on radiation effects, however much of this is also offset by more complex circuitry and more failure mechanisms. Most military satellites (particularly those in our Nuclear command & control system like Advanced EHF and SBIRS) would likely be ok at least in the near term, but it’s likely that commercial satellites, like Starlink, would be extensively damaged. The effects of this are hard to predict without some knowledge of timing, altitude, weapon yield and other environmental effects like solar radiation patterns that impact the Van Allen belts. But needless to say, I don’t think this is an area where we want to F around and find out.
History of nuclear reactors in space
One other hypothesis was that the Russians had a nuclear reactor powering a powerful jammer or some other payload. The US, China, the Indians and the Russians have all flown nuclear power sources in space before. Rather than focusing on the particular missions that might be enabled by that kind of power source (which could be an entire series of posts by itself), I’ll focus on the reactors themselves to stay on topic here.
The most popular nuclear reactor is actually not a true fission pile style reactor but rather a so-called Radioactive isotope thermal generator or RTG which is used in a number deep space probes going to the outer solar system where solar radiation to power their payloads is extremely scarce. Close to three dozen of these systems have been launched in the last 60 years, including use on the Apollo Lunar Landers, and several are still operational nearly 50 years after launch (Voyager 1 & Voyager 2 were launched in 1977 and as of this writing are still online in a limited capacity).
While the US flirted with flying more traditional fission reactors with the SNAP-10A program in 1965 (which actually put a nuclear reactor pumping an ion engine on orbit that worked for 43 days), it was really the Soviets who did the most work on this under their RORSAT program. RORSAT put 38 nuclear powered satellites on orbit between 1968 and 1988, which were mostly powered by the BES-5 category of reactors. These satellites were used for ocean surveillance via radar and the nuclear reactor was intended to allow to operate without solar panels that could create drag and to do so without consideration for day or night conditions.
The reactors for these satellites generated an eyepopping 100 kW of thermal power which was converted through thermodynamic means (by pumping a liquid metal working fluid) into about 2-3 kw of electrical power. The high paradigm of efficiency! As a spacecraft systems engineer - the thought of getting rid of 97 kW of thermal dissipation is kind of daunting but I’m sure some enterprising Soviet engineer found a brute force way to make it happen.
The Russians inherited the Soviets space nuclear program and continued to evolve and fly new reactors under the TOPAZ name, even selling some to the US for research in the 90s after the Cold War ended. What’s unclear to me however is if they continued building these given the dwindling Russian space program in the last couple of decades (until a few years ago when they started trying to weaponize space). It’s likely the case that much of the expertise to build these reactors was lost as the engineers aged out of the Cosmodrome in the last two decades. Perhaps the program that Rep. Mike Turner was worried about was to restart this work with the hope of using nuclear reactors again on orbit for more powerful missions and propulsion? I’m only speculating here.
Soviet space nuclear incidents
The Soviets’ defunct BES-5 program has caused a recurrent environmental headache decades after it ended, and has basically turned a number of orbits into superfund sites as the reactors leak coolant comprised of liquid metal that turns into droplets that are debris that must be now tracked and avoided by other spacecraft flying through the same volume. While in theory the satellites were supposed to eject the reactors into a higher orbit prior to being de-orbited, in practice their reliability led to several incidents. The most famous incident involved the de-orbiting of Kosmos-954 ,which spread radioactive debris over Canada upon reentry in 1978. The cleanup effort for this one was so large the Canadians actually billed the Soviets $6 million for the clean up.
Another subsequent incident in 1982, Kosmos-1402 also led to the breakup of it’s core over the South Atlantic and Indian Oceans. This one scattered debris all over the planet to the point that Strontium from the reactor core was actually detected in rainwater in Arkansas. The Soviets paused all nuclear launches for a year and a half after the incident while they perfected the reactor design so it wouldn’t happen again.
Nuclear Propulsion: Project Orion, Project Draco, Dark Fission
Perhaps the most famous example of nuclear propulsion in Space stemmed form Project Orion a mostly paper study done by NASA, DARPA and others in the 1960s that looked into the possibility of propelling a spacecraft forward by igniting nuclear explosions that would propel a spacecraft forward by pushing on a “push plate” designed to insulate it from the blast. This idea quickly fell out of favor as the Partial Nuclear Test Ban Treaty and Outer Space Treaty banned the detonation of nuclear devices in space.
There has been renewed interest in nuclear propulsion in the last 10 years from DARPA as translunar missions and possibly missions to the Mars and further have become more common. Nuclear reactors and the continuous and stable power they provide could enable the operation of much larger electrical propulsion systems than are currently in use today, enabling much more rapid transfer to high orbits by orbital transfer vehicles (OTVs, i.e. space tugs like Astroscale or Momentus Space) that would have to carry a lot less fuel and would be able to use the additional power to generate considerable more thrust. Today orbit transfers using these OTVs on SpaceX launches like Falcon 9 can take weeks or even months after initial launch for many lower cost satellites using rideshare and other services. Nuclear powered electric propulsion could shave this time down to hours and trips to the moon to a day or less.
DARPA recently started a program (in collaboration with NASA) called Demonstration Rocket for Agile Cislunar Operations (DRACO) that was awarded to Lockheed Martin early last year. The Lockheed Martin award is for hundreds of millions over the full life of the program and may get to orbit by 2028 - maybe. There is also a start up competitor called Dark Fission with some very top shelf folks from DARPA, Astra and others (Dr. Fred Kennedy, who was the founding director of the Space Development Agency and a former DARPA TTO office director is CEO) that is aiming to get there even sooner and for far less money. Once again a start up witha more focused mission, more dedicated team and no big prime bureaucracy/brain damage to contend with takes on a big prime like David & Goliath. Let’s see who gets there first!
Conclusion
The most likely use forthe uncovered Russian project was either a nuclear bomb intended to be orbited to produce a high-altitude EMP effect at a strategically appropriate time or its meant to provide a “Doctor Strangelove Doomsday Device” like effect of wiping out a large number of satellites (with no consideration to nationality) in LEO orbit through the radiation it would accumulate in the Van Allen belts via the Christofilos effect.
The other options seem to lack utility given that modern solar power and battery systems for satellites can easily achieve the several kilowatts to tens of kilowatts of power (a large Boeing 702 bus can run 12-25 KW total available power) you would pull from a nuclear reactor without the controversy and disposal issues. It’s possible it could be a form of nuclear propulsion, which we are also investigating, but it’s unlikely given their budget and objectives.
Post Script: Trinity and Beyond - The Atomic Bomb Movie
If you haven’t watched Trinity and Beyond: the Atomic Bomb Movie, you really should. It’s one of the best documentaries on the Cold War ever made. It’s narrated by William Shatner and directed by Nicholas Meyer (who directed Star Trek II and Star Trek VI among other films). In high school I made a video intro in Avid on the SIOP using footage from this (and a few other sources) set to the tune of 46&2 by Tool. My classmates all kind of looked at me funny afterwards (mostly because Bob Schwartz the civics teacher called me out for playing air guitar in the back of the room during the video). Available now in full length on Youtube: