# How would a civilization protect a Dyson swarm from solar flares and coronal mass ejections?

This is the first of two questions. Same introduction.

A civilization on Earth has just begun expanding with a Dyson swarm, which is a Dyson sphere but made with many satellites, to prevent structural problems a sphere would have. This will generate a lot of electricity for the population.

I was reading some articles about solar flares and it got me thinking. How would a Dyson swarm react to solar flares and coronal mass ejections? Solar flares, Coronal mass ejections, and the like can cause havoc for electrical systems. This is because an abundance of energy is pushed onto the electrical circuits thanks to mostly magnetic induction, with a great potential to cause damage. On Earth and a lot of the orbit we're relatively well protected from the direct effects of a solar flare thanks to the magnetism of the Earth, but closer to the sun not so much.

A Dyson swarm is relatively close to the sun and has no Earth magnetism to rely on. How would you defend a Dyson swarm against Coronal mass ejections, solar flares, and the like?

In some other threads, I saw a lot of ideas with water or simply protection with a lot of dirt. To make sure it is well understood, the Dyson swarm is meant to make a lot of energy as efficient as possible. That is why the best answer tells the most efficient way of protection against big coronal mass ejections and the like. That means the satellites are preferable as light as possible, with as little complexity as possible, with as little loss of energy gathering efficiency as possible. 'Protection' can mean that you replace parts or satellites if they get damaged if you can support this with why it is most efficient.

I'm well aware that this is a depth not suited for my short story, adding problems that aren't there for most readers, but I'm very interested in it anyway. Even if it's only mentioned in passing, I would like it to be correct.

• Idk, as u ask somewhat engeneering question, u could link few papers on how strong those shtorms are, as honestly it does not look like a big or universal(design independant) problem. There are satelites which work for ages, and what do we see is "metalized mylar foil" which forms few types of insulation which seems to be sufficient with those particular designs. In some cases it may short your solar panels but have zero effect on mirror based solutions. Protect electronic brains of setup for that regular solutions used in satelites can be directly borrowed, so look how sats do that May 11 at 22:58
• Realizing that I may be ask too much, but at least link to wiki and more importantly, as it is engenering, which particular design of nodes did u choose May 11 at 23:09

# Acceptable Losses

It's a Dyson Swarm, a prototypical megastructure. You're churning out millions (or tens of millions) of satellites. Why bother avoiding or hardening against coronal mass ejections; collect the roasted satellites for materials and launch replacements.

It's basically the datacentre drive replacement problem. Rather than make things more durable/able to avoid CMEs, just accept that a portion of your satellites will be knocked offline at regular intervals, build redundancy into your network, and have a steady stream of replacements.

• I like the comparison to datacenters. Of course the next questions highly depend on the density of the satellites, but wouldn't a similar thing like the Kessler syndome happen if you would try to just replace it? And wouldn't a single solar flare easily fry a huge degree of satellites around the sun, resulting in possibly billions of satellites lost? And at a time where solar flares are extra busy, wouldn't this fry way too big a percentage? May 11 at 17:23
• @Trioxidane - I did specify "collect the materials for recycling", so no Kessler syndrome. CMEs and solar flares are not the same thing - if a solar flare fries your satellites, you're building them too weak. And CMEs do not occupy many degrees of arc. And yes, it depends on the density. If you've got quadrillions of satellites around the sun, then a CME might fry billions, but that'd still be a fraction of a fraction of 1% of the total, and you should be expected to produce replacements in a day. May 11 at 17:36
• Same as Trioxidane, I do appriciate replace concept, but the problem I see with the answer is complete lack of efforts to look at how big the actual problem is, and how it is solved, or what it takes to solve in typical satelite. Sure the the good thing is it is an universal approach, but alos it is where good stuff ends. May 11 at 23:14
• @MolbOrg - the amount of extra material required to shield a satellite (most of which would never get hit by a CME!) against a CME would radically increase your total mass budget. You're going to have to repair or replace millions of Dyson swarm satellites annually anyway, so this is just more attrition. May 12 at 0:49
• I guess, your impression of dswarm nodes aka satelites is off as well, even if there are multiple options, necessity to have something which captures incoming light, it can't be removed, so as radiators so as energy conversion equipment, it kg's per square meter. But besides that, I may have wrong impression, but I alreaday hinted standart sat solutions. Sure some repair and replace will have place, do not say what u said is wrong, it is not wrong, it quite general strategy which does not depend are there cme's or not. So not wrong but more suitable to be A for more general Q May 12 at 1:50

Individual magnetic fields.

Each satellite protects itself the same way that the earth does: with a magnetic field. The individual satellites generate magnetic fields all of the time through their normal operation. If there is predicted to be a huge outpouring of charged particles from the star, the satellites strengthen their fields. These fields extend out some distance from the satellites and divert charged particles entering them.

During this process the satellites might transmit less energy home. Do not begrudge that energy, fat and sassy Earth folks! Your hardworking satellites need it to stay safe.

• The only legit answer atm, even if it is a half of it which is sat design independant one. But also lack of effort in looking in the numbers related to the problem and of existing solutions. May 11 at 23:17

Why not designing the swarm to take advantage of that bonanza of energy being tossed at it?

Solar eruptions are bound to happen, so if one designs dedicated circuitry to capture that energy instead of avoiding it, it will make for a nice bonus on the produced energy, and will surely compensate for the added complexity to the overall architecture.

Compare this with adding what is basically passive ballast and waste that energy.

• If you can support this with a way how to, while not or only impeding the satellites in a minor way in their normal solar collection, I'm all ears. You can post the same answer to the second question while you're at it ;) May 11 at 16:28
• I think you overestimate the relative energy of solar flares. Our sun produces $10^{26}$ Joules per second. The average solar flare, at its most frequent, occurs a few times a day and produces $10^{20}$ Joules. Solar flares are completely dwarfed by standard solar output in terms of harvestable energy, by a factor of at least $10^{5}$ (assuming pessimistic dyson swarm efficiency, and extremely optimistic solar-flare harvesting efficiency) May 11 at 21:35

## With magnets, of course!

You can protect the Dyson sphere the same way you can protect the planet. While it doesn't have a magnetic field by default, nothing stops you from generating one artificially (furthermore you can generate fields much stronger than planetary ones). Even more, CME is basically the sun throwing matter at you for free. Use magnets to channel the plasma into your starlifting facilities to turn it to use. One of the proposed starlifting techniques actually relies on creating a constant unending coronal ejection spot, by heating the surface of the star with lasers.