I'm in the process of inventing a method of powering the onboard systems of a space ship. This excludes engines and maneuvering thrusters. The idea I'm working on involves killer electrons.

High-energy ‘relativistic’ electrons, often called “killer” electrons, are a major source of radiation damage to satellites so understanding their patterns of activity is crucial. Solar emissions of charged particles and magnetic fields can disrupt Earth’s magnetic shield, leading to geomagnetic disturbances. Amid such occurrences, the number of killer electrons in the external radiation belt can surge exponentially, posing a considerable space weather threat. (Source)

Intense solar activity can disrupt the Van Allen belts, and Cluster made another vital discovery when it was on hand to observe directly the effects of a particularly strong solar shock wave hitting the magnetosphere in 2004.

It saw the creation of killer electrons through what turns out to be a two-step process. The electrons are initially accelerated by the shock wave compressing Earth’s magnetic field. Then Earth’s magnetic lines wobble, creating something like a very large-scale, low frequency laser, which accelerates the electrons even more, up to ‘killer’ energies. (Source)

The Preliminaries: The idea I'm developing is described as a turbine. Bussard-style collectors are used to capture killer electrons. The electrons are channeled into the "turbine" where their motion through the turbine creates killer-grade magnetic fields which are then used in the usual way to create non-killer electricity to power my universe's glorious future. The operation of the turbine itself is not specifically relevant to the question. How the turbine gets the killer electrons, is.

My story needs a repair opportunity. The flow of electricity is disturbed and something must be done about it. I'd like that repair to occur at the interface between the collectors and the turbine. It's tough to repair technobabble, so I'm trying to develop a rationalization for this interface. Magnetic scoop channels the electrons into the interface and as they exit the interface they're in a highly conductive material. But how does one get over-active elecrons from free space into the conductors?

Conceits: I'm handwaving the availability of killer electrons in outer space. I've not found studies indicating the quantity, if any, of killer electrons outside the Van Allen radiation belts. No one really has a reason to look because the problem driving research is keeping satellites alive. I'm asserting as a rule of my universe that over the course of a dozen billion years the universe has been charged with an adequate supply of the little whompers.

I'm also handwaving the complete failure of my turbine to abide by the first law of thermodynamics. I'm using the collected energy of killer electrons to power both the ship and the capture of killer electrons. I'm sure that's a perpetual motion machine. I'm ignoring this.

Finally, how the bussard-style collectors successfully capture over-charged electrons moving at near the speed of light is not relevant to this question. If mother Earth can move them around, so can my collectors. Just assume they work. So say we all.

Question: How can the killer electrons collected by the bussard collectors be handed off to the conductors in the turbine?

  • $\begingroup$ Any answer should determine the rate electrons pass through a given part of space during a storm. You may like this (frontiersin.org/articles/10.3389/fspas.2023.1168636/full) article; although I can make heads nor tails of it I see things like "electron density" and electron counts per cubic centimeter, which when combined with these electrons moving at speeds we know may allow you to determine the rate at which electrons pass through a given portion of space and therefore the amount of harvestable energy per time unit. I also recommend looking up "triboelectric nanogenerator". $\endgroup$
    Commented Dec 27, 2023 at 1:14
  • $\begingroup$ @KEY_ABRADE That's an interesting article that I'll read in greater detail. However, as an ex-chip designer, it's not necessary to know the specific current density of a power source to determine methods of moving electrons from the aluminum common to routing between IC components and SiO2 gates. In other words, I don't need the detail you're suggesting is required and I believe based on my experience that it's unecessary to know it to suggest possible solutions. $\endgroup$
    – JBH
    Commented Dec 27, 2023 at 1:41
  • $\begingroup$ In other words, it's not about how much water goes through the dam but about how fast the turbines can spin. That makes more sense, which of course means I know even less about it. Also, my understanding is that if the energy needed to maintain the Bussard is less than that harvested from braking electrons, this is not a perpetual motion machine and therefore does not violate the first law. This is still up in the air, of course, as this power source is based on high-velocity electrons whereas the classical Bussard ramjet uses fusion, but it may still copper-bottom your handwave a little more. $\endgroup$
    Commented Dec 27, 2023 at 1:46
  • $\begingroup$ @KEY_ABRADE You're worrie about issues that don't pertain to the question. To use a metaphor, I need to condense water vapor and move it into pipes. The Collectors bring the vapor to the interface, the pipes take the condensed water away... how to condense the water? Please focus only on that aspect of my question which, to extend the metaphor, doesn't rely on knowing the quantity of water nor its velocity. $\endgroup$
    – JBH
    Commented Dec 27, 2023 at 1:49
  • $\begingroup$ As an aside you might be interested in the enzyme ATP synthase that is a molecular scale turbine operated by the flow of hydrogen ions through it. en.wikipedia.org/wiki/ATP_synthase $\endgroup$
    – Slarty
    Commented Dec 27, 2023 at 17:52

2 Answers 2


Extra dimensions

String theories say that the Universe actually has 10, 11 or 26 dimensions depending on the one that you choose to use. Four of those dimensions are space and time as we know them, the rest are too compact for us to experience them.

Particularly relevant to this question is the Kaluza-Klein theory:

In physics, Kaluza–Klein theory (KK theory) is a classical unified field theory of gravitation and electromagnetism built around the idea of a fifth dimension beyond the common 4D of space and time and considered an important precursor to string theory. In their setup, the vacuum has the usual 3 dimensions of space and one dimension of time but with another microscopic extra spatial dimension in the shape of a tiny circle.

(...a metric ton of mathing and nerding...)

Kaluza presented a purely classical extension of general relativity to 5D, with a metric tensor of 15 components. Ten components are identified with the 4D spacetime metric, four components with the electromagnetic vector potential, and one component with an unidentified scalar field sometimes called the "radion" or the "dilaton". Correspondingly, the 5D Einstein equations yield the 4D Einstein field equations, the Maxwell equations for the electromagnetic field, and an equation for the scalar field.

In plain English: by applying general relativity to a universe with five dimensions - length, width, height, time, and an unnamed one which is minuscule and looped - dudes were able to output the original Einstein field equations AND the ones for electromagnetism. This extra dimension is very in line with those extra ones described by string theory.

We could say that the electromagnetic force moves through this dimension.

Now, sufficiently advanced technology is kinda like magic... So an interstellar civilization might be able to technomagically manipulate the flow of the electromagnetic force in this dimension, or even make it move through other dimensions. The ship might be built in such a way that it has "force lines" projecting very intense electromagnetic fields in the classic 4D space around it, with such fields being shaped and directed through these extra, looped, microscopic dimensions. Any electron colliding with the hull at any point and coming from any direction is immediately trapped and follows a virtual track that eventually leads to the turbine. From the electron's point of view, it is following an inevitable path just like a mass falling into a black hole (with a turbine replacing a singularity).

Since the lines are space permanently bent into a shape, it shouldn't cost any (or at least much) energy to keep this effect going.

  • 1
    $\begingroup$ That was... a spectacularly good idea. +1. I'd give you another +1 for the phrase "a metric ton of mathing and nerding" but our SE Overlords in their infinite wisdom won't let me do that. So, kudos for making me chuckle. $\endgroup$
    – JBH
    Commented Dec 27, 2023 at 18:47

Just Smash 'Em

"High Energy" just means "Fast."

A High Energy Electron is an electron moving at some significant fraction of the speed of light.

If you've got a stream of fast electrons, an easy way to turn that into electrical energy is to slow them down! Direct the beam of high energy electrons onto one side of a thermocouple. As the electrons hit the conductor, they will slow down, transforming the KE of the electron into heat energy within the thermocouple.

A difference in temperature across the thermocouple drives an electric current.

You've effectively created an RTG, where you've replaced the radioisotope with an electron beam.

Wear and Tear

Now high energy electrons are going to do interesting things to your thermocouple. You're likely to cause nuclear sputtering, and other exotic atomic interactions. The good news is most of these interactions will create more heat! The bad news is that this degrades your thermocouple over time.

This gives you a couple of potential repair problems for your story.

  1. The system trades out thermocouples periodically so that the radioisotopes can decay away, and the swap out mechanism is broken.
  2. The thermocouple has separated. A thermocouple requires two dissimilar conductors to be in contact. Perhaps they have warped to the point they are no longer making a good connection.
  3. Beam mis-alignment. Your electron beam was mis-aimed for a short time, and now the power distribution system is mildly-radioactive and damaged.
  4. Other

The fun part about all these problems is that your equipment is radioactive, so you get an immediate plot point in that the heroes want to complete their repair without frying themselves.


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