Submitted by Pornelius_McSucc t3_113l5ul in space
So I've been doing a lot of surfing, looking at the fact that Mars for example has no magnetosphere, and a "dead" core that is not hot enough and/or doesn't spin independently to the other planetary layers. I saw that some people theorized we could detonate a large nuclear fusion payload inside the core (assuming we are able to reach it) to "restart" the magnetic dynamo effect by reheating the core layers so convection can occur. People usually point out that this would probably just make a mess instead of a magnetic field, because it wouldn't create spin on the core, due to the fact that is only generated by a moon of significant mass.
So theoretically, would it be possible to
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Bring Ceres to Mars to provide tidal stress on the core and establish an independent spin
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Nuke the core with a high-efficiency fusion bomb to liquefy it all enough for magnetic convection
?
The same principle could possibly be used to bring Mercury to Venus and spin the planet's core as well. Venus already has plenty of geothermal energy, but none of it spins to create magnetism. Ofc Venus is different, Mars and Earth coincidentally rotate at almost the same rate but Venus barely does at all. So we may have to first tackle the hurdle of accelerating the rotation, I saw some things about how potentially orbiting something around it at 10 percent lightspeed could do that in 30 years.
The only other rocky bodies with significant magnetic fields are Ganymede and Triton. I'm not sure if Ganymede's is strong enough to protect its surface from the radiation of Jupiter though. But we could use Ganymede to study how we can get a magnetic field on a similarly sized object like Mars. Personally I think figuring out how to do it organically like this is a cooler option than having something at L1 generating its own electromagnetosphere, regardless of the short-term practical superiority and necessity. Mostly I think this because an artificial magnetic field would require a ton of energy to maintain and it may be prone to mechanical failure. Another reason is that if we were to accomplish a core restart it would keep the planet inhabitable regardless of the state our species is in. A superconductor belt is a cool idea though.
Also I'm kinda fuzzy on what exactly creates a planetary magnetic field. If it was simply tidal forces and heat required we would probably see more bodies with a magnetic field, (Titan, Io) so. I saw people discuss how it is possible Earth's core just has a lot of radioactive material creating a georeactor, separating us. If that is true we would need to buy time on the geological scale by injecting massive amounts of radioactive material into a core (not feasible). Maybe we will never really know until we are able to do in-depth geological surveys on these planets. Edit on this section: After further googling it appears several bodies under notable tidal stress like Io and Enceladus are thought to have their own magnetic field. I'm not sure what that entails for the potential necessity of a georeactor. It may discount the necessity entirely.
So I'm really just curious if y'all believe it is theoretically possible to organically jump start and maintain a planetary dynamo. Please keep in mind that I don't really care about how ridiculously implausible it is for our current civilization and tech to achieve, I'm just interested in the theoretical. I feel like if we can figure this out, then humanity in say 2,000 years could be living across 3 Earths in our system with Venus and Mars both terraformed. That'd be crazy.
Edit: Guys, the core process that creates a magnetic field. Terraforming that. Not installing an artificial one. That is not the point of the discussion. And again, pretty obvious we can't do this currently. This is a hypothetical and theoretical prospect, made available by the logical assumption that a technological path exists to this level of planetary manipulation. Like we can't invent something that will accelerate to past light speed, so there is no use discussing that. But we can technically enact these immense methods of terraforming with the understanding of planetary dynamo mechanics. Talk about that please.
Edit 2: so happy this got even a little traction ive been obsessed with this. Everyone discussing it is a little dream of mine realized.
zolikk t1_j8r3yvs wrote
I understand what you're asking and it's not an artificial field. I don't know how possible it is, but my question is why? An artificial magnetosphere is probably much easier, so why bother with a "terraformed" one?
Better yet, why make one at all? You do not need a magnetosphere to terraform the surface of Mars otherwise. You'd only care about it if you want the changes to become more or less permanent without maintenance. But why would you bother? If we are able to create livable conditions on the Martian surface in the span of centuries only, then we don't care if those conditions are stable over only millions, rather than billions, of years. We can just actively maintain them as needed.