It has been far too long. I had some very interesting things happening in my life. They were and are very nice. In the last months I have come to work on Nahual a lot more again. I have understood a lot more about the space weather modeling framework (SWMF) and specifically the global magnetosphere (GM) simulation I am mainly using.
A short wrap-up from the past: I want to make a proposal for a satellite, which is able to protect the atmosphere of planet Mars from solar wind, if we ever decide to terraform it. Mars does not have a natural magnetic field as the Earth has. The SWMF allows simulations of the solar wind plasma.
For this article I have simulated a magnetic satellite with 17km diameter and a varying magnetic field strength of 10, 20 and 30T at the Sun-Mars L1 Lagrange point. Everything in this simulation is measured in Mars radii R (3.400km). Every dot represents a cell with data. The dots are colored based on the particle density in each cell. Blue means few particles, red means many particles. We want blue cells around Mars (the single red dot at the center).
While 17km and 10T are still very huge, seeing the size of the perturbations on an object “just” 17km wide, gives me hope to look for a smaller solution. It is worth noting, that I experienced a lot stronger perturbations on simulations with higher resolution. I use these images to understand the produced simulation data. But since a simulation is solely based on my input parameters, they are probably still quite some steps away from showing a realistic simulation.
On earlier simulations as well as this simulation I found, that the perturbations tend to weaken downstream. The images show a very strong reduction in density close to the magnetic field, but not very far behind. Due to this, I revised the original idea of putting something at the L1-Lagrange of Sun and Mars. With a bit of help of an AI I thought about alternative solutions. Currently I simulate with 10R (34.000km) distance to the planet. The strategy would be three or more identical satellites with excentric sun-synchronous orbits with its apogee (highest point) facing the sun. Sun-synchronous orbits wander over the year, due to some planets not being perfect spheres, and stay between Sun and planet. However, since it only stays there for a given amount of time before going into the shadow of the planet, more satellites are required. As an advantage, the orbits are easier to navigate than Lagrange orbits and are reasonably stable against the expected solar wind magnetic pressure, which is small but not negligible. The force on the satellites at the “day-side” of this eccentric orbit is less influential as the force negates itself over time or exerts tangential at apogee.
There are a lot of questions remaining, that need an answer. And as it is with science, when you solve one, you get more new questions. They are not solved by plasma simulations alone, but I will follow the main route for the moment. Some of the questions boggling me:
– Is a low-pressure low-density zone in this simulation sufficient to protect an atmosphere? Or are there also other effects at play?
– What magnet size will be reasonably doable? I will see whether I can push down to below 1km construction diameter. Is a magnet that small in size able to create the needed plasma perturbations?
– Is a shield necessary in the first place? While the solar wind degrades atmospheres, this might take millions of years to do so. Maybe terraforming the Mars wouldn’t even need it, as the erosion is neglegible anyway.
I am already advancing further than in this blog post, but I needed to start somewhere again. So there will be more to share eventually. Looking forward.
Direct link to article and comments: https://nahual.eu/first-simulations/
Download files: https://nahual.eu/wp-content/uploads/2026/05/First-simulations.zip
