I'm trying to create a universe that is grounded in reality but still interesting and exciting like a traditional sci-fi story.
In my setting, particle weapons (like in "Star Wars" or "Star Trek") are the most common form of weapons.
I have a couple of questions about them.

Firstly, in fictional media, particle beams or particle bolts are usually highly visible. Is there a plausible reason for having such them be visible, even in space? Would the type of particle, environment or weapon design be a factor at all?

Secondly, and this is something I've been wondering for a while, would a shot from a particle weapon (like a "Star Wars" blaster bolt or "Star Trek" phaser beam) create a sonic boom in an atmosphere?

Please don't be TOO harsh on me. I'm not a scientist, just a very insecure writer. :)

Thank you.

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    $\begingroup$ It's worth doing research into the particulars of each setting. Star Wars weaponry is almost entirely plasma-based (at least it is these days), which explains a lot of the finer details, such as the fact that you can see them, even in space, because plasma generates photons. Star Trek phasers uses 'nadions', which is entirely fictional and thus gets to follow its own rules. As far as sonic booms go - well, modern handguns can actually create sonic booms, so presumably yes, but it would depend on the ammunition type and rate of fire. $\endgroup$
    – Halfthawed
    Jul 5, 2020 at 14:29
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    $\begingroup$ Speaking for myself, I usually take "particle weapons" as code for "don't examine the physics of this too closely (because it won't work), just roll with it". $\endgroup$
    – Cadence
    Jul 5, 2020 at 16:32
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    $\begingroup$ Star Wars is not science-fiction, it is a fantastic fairy tale; it was never intended to be taken as science-fiction. In the words of George Lucas himself: "I knew from the beginning that I was not doing science fiction. I was doing a space opera, a fantasy film, a mythological piece, a fairy tale. I really thought I needed to establish from the start that this was a completely made up world so that I could do anything I wanted." $\endgroup$
    – AlexP
    Jul 5, 2020 at 17:47
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    $\begingroup$ @AlexP Right, and then when the tie-in books came out they recruited some really good sci-fi writers who tried their best to slap some sense back into the sci-fi - the best example is Han's claim of 'made the Kessel Run in under 12 parsecs' was retconned to involve skirting a black hole cluster to have the measurement of space make sense. There's actually a lot of good science fiction in Star Wars, but only if you know where to look. (Mostly in the tie-in books.) $\endgroup$
    – Halfthawed
    Jul 5, 2020 at 18:39
  • $\begingroup$ @Halfthawed: Sorry, I should have made it explicit that by Star Wars I mean the three Star Wars films. (Yes, there are more films now, but I am no longer at the appropriate age to enjoy modernist fairy tales.) I am not even sure that the countless books are to be taken as being part of the same cycle; they are written by many different authors, they have no unifying theme, and the current management of the franchise is apparently firmly set on disregarding them. $\endgroup$
    – AlexP
    Jul 5, 2020 at 19:04

2 Answers 2


/highly visible/

To be visible the beam must either give off light itself, or excite the medium it is traveling through to give off light. In an atmosphere that would be the air. If the particles were dropping off energy in the air it could heat the air to glowing: this would be flames. If the particles very rapidly heated the air that would be analogous to lightning, and the rapid movement of air would be analogous to thunder. https://en.wikipedia.org/wiki/Thunder

The sudden increase in pressure and temperature from lightning produces rapid expansion of the air within and surrounding the path of a lightning strike. In turn, this expansion of air creates a sonic shock wave, often referred to as a "thunderclap" or "peal of thunder".

As regards being visible in space, radiation to make them visible would have to come from the particle themselves. If you had enough mass of particles, perhaps in the process of their acceleration they would emit black body radiation according to their temperature.


A bolt of particle radiation would start out appearing white and then become redder as its constituent particles cooler during their journey. In a vacuum when the bolt became invisible because the particles had cooled they would have not lost any of their destructive power. You would need a metric boatload of particles for their glow to be visible in space. Your particle beam will converge on a superpowered shotgun shooting sand. More likely the particles would be less numerous and invisible.

If you used radon as your particle (as suggested below) or added some other intrinsically radioactive element you could follow the path of your beam if you had a device which could "see" in the frequencies emitted; alpha particles if you use radon or you could dope your ray with cobalt or some other gamma ray emitter. Making these radioactive elements should not be tough since your particle beam presumably works like a cyclotron.

Particle radiation can traverse matter in its path, like the atmosphere, or a body. Or your target. The place where most energy is dropped off is determined by the mass of the particle (proton? carbon ion? radon ion?) and the charge of the particle which mediates much of the interaction between particle and medium/. That place is called the Bragg peak. To get your shot thru the atmosphere but stopping in your target means you will need to aim in 3 dimensions: both the 2 dimensions of your plane of view and also the distance to the target where you want your particle to drop its energy. You will need to take into consideration what you are shooting thru. It is not outrageous to shoot at a target deep in the water or underground if you can make the particles energetic enough to traverse those media.

More on those matters at this question: What subatomic particle is best for a particle accelerator gun?

Not to Bragg but here is a short fiction I wrote where a guy has a particle beam. https://www.fictionpress.com/s/3342628/1/Particle-Beam


Check out 2 websites: 'Tough SF and 'Atomic rockets' for details on space based particle and laser weapons Plus missiles and and other concepts). There are examples of different potential types of energy weapons and discussions of the engineering and energy requirements of each. Plus comments on their relative merits as potential weapon systems.

The NASA NIAC Program (NASA Innovative Advanced Concepts) on laser coupled particle beams is especially interesting as it would seem to give superior performance (range) than either a laser or a particle beam weapon ever could as well as being useful of propulsion purposes.


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