So having read a couple of other questions on here, and postulating over this for a while, here's my question.

Is it possible to have two magnetars in a distant binary orbit, with an earthlike planet in between them at the orbital center?

The goals of this world:

The planet is split in two, and stable. Strong magnetic fields produce wild and dangerous weather, and the ability to sail through the air by riding the field for buoyancy. This also allows for heavier than air creatures like dragons to work, since they could just have some form of strong natural magnetic field.

Absolute science is not necessary, I'm looking to make this plausibly accurate, since of course this could never occur in nature.

EDIT: I'm assuming I can avoid the gravitational problem due to a number of factors. Firstly, the core was split in half as well, and the liquid part would flow together faster than the solid part. Without as much pressure, the two halves of the solid core in an hourglass shaped liquid core would produce some weird effects as well. Also, the two halves are only a couple miles apart. So water and air fall down between, but water is vaporized and air is heated, leading to them both floating back up. Aside from a spectacular set of falls near every ocean, and a perpetual mist rising from the crevice, I'd like to keep the rest of the physics reasons for the halves not smashing together mostly absent.

My hope is that having it suspended between two magnetars allows the two halves to remain separate and stable. Perhaps the split is not complete, or was and the mantle merged before the crust? here's no in world time limit on this stabilizing. Just so long as I have a reason it IS stable.

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    $\begingroup$ When you say 'split in two', you mean like two half-planets right next to each other? Not touching at all? $\endgroup$ – DaaaahWhoosh Aug 24 '15 at 19:01
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    $\begingroup$ Could you clarify what a MagStar is? My Google search just turned up computer technology and business websites. $\endgroup$ – Frostfyre Aug 24 '15 at 19:09
  • $\begingroup$ @Frostfyre Probably supposed to be a magnetar. $\endgroup$ – Samuel Aug 24 '15 at 19:21
  • $\begingroup$ The planet is like cutting an apple in half and putting both parts next to each other? If so, then, no, it would not be stable: the halves would fall to each other. $\endgroup$ – Mikey Aug 24 '15 at 19:37
  • $\begingroup$ @Samuel My first thought was a magnetar. I think they're fun, since they can rip apart atoms. But the OP has given them a different name, so they could be a new breed of star in-universe. $\endgroup$ – Frostfyre Aug 24 '15 at 19:38

What you are describing is impossible, I'm sorry. At the temperatures and pressures involved the rock will flow like water and compress down into a near sphere. An incredibly powerful magnetic field would cause anything affected by the magnets to pull towards the fields but everything else would still flow around them. It would also be unstable, either the magnet wins or gravity wins.

The only way to make this happen is to somehow shape the gravitational field in the area or have something incredibly strong pushing the halves apart.

The simplest way would be to have two planets (each spherical) next to each other orbiting a combined center. See Rocheworld for example.

To give a "cut apple" effect though you will need an alien race to use some beyond-current-conception (i.e. magic) technology to make it happen. Throw in some techno-babble about gravitational fields, spacetime curvature, matter repulsing fields, or something and leave it at that.

Keep in mind though that you would not have waterfalls/atmosphere/etc rushing into the crevice. Whatever is repelling the ground will repel that just as well.


The impossibility of hemispherical planets aside, any planet close enough to a magnetar that its magnetic field (somehow) overrides gravity itself would be utterly, utterly, inhospitable.

Magnetars are known to produce gamma-ray bursts and x-rays. Caught between two sources, such a planet would find its atmosphere converted to a nitric acid bath. Lacking a magnetic field of its own – you split the core, remember – the planet would be stripped of lighter molecular gases (particularly hydrogen), losing all water vapour (H$_2$O) and all protection from x-rays. Your impossible planet would be barren.


If stars (or anything outside of the planet itself) are supplying the magnetic force to keep the two halves apart, the planet must rotate exactly once per orbit or it doesn't work. Otherwise, as soon as the split was perpendicular to the magnetic body, the gap would close.

It would be much more plausible (though still quite a stretch) if the two halves themselves were magnetically charged and repelling each other just enough that they split apart for a few miles before gravity creates an equilibrium. I would focus on imagining the event that split the planet and then give it a neodymium-rich core to maximize the magnetic force. Whatever origin event you come up with would need to split the planet cleanly and instantly polarize the two halves.

  • $\begingroup$ I'd like the event that split the planet to be some form of super-science from the far future. Is it feasible to have some sort of beam weapon that slices and polarizes? $\endgroup$ – nightninja Aug 25 '15 at 12:18
  • $\begingroup$ In super-science from the far future, anything is feasible! (Well, almost.) I couldn't tell you any currently known energy or technology that this super-science might be based on, but if you're willing to invent a word and say your event was caused by a(n) [invented word] {ray/wave/beam/etc.} which split and polarized the planet, that should be enough to explain your planet. $\endgroup$ – Josh Aug 25 '15 at 12:50
  • $\begingroup$ Since all magnets have 2 poles, all the two repelling halves need do is for one to do a half rotation and they will be attracted back together. $\endgroup$ – Oldcat Aug 25 '15 at 17:36
  • $\begingroup$ @Oldcat, based on the OP, I believe that the two halves are so close that there physically isn't room for them to rotate independently from one another. This, combined with the fact that they were originally one mass rotating around its center, means that the two halves should continue rotating around their common center of gravity. $\endgroup$ – Josh Aug 25 '15 at 22:47
  • $\begingroup$ one could rotate around an axis perpendicular to the current axis of rotation and still flip with that constraint. So lets say it is cut on the international date line. The Western hemisphere north pole could move south down that longitude and there would be no restraint until the poles flipped and they attracted. $\endgroup$ – Oldcat Aug 25 '15 at 23:15

My world-building advice to you is to give up on trying to shoehorn the products of your imagination into the limitations of real-world science.

Your scenario seems pretty implausible from a scientific point of view, so much so that its not really worth trying to point out the errors. But it is worthwhile advise you to just ignore science and let your creation flow unhindered.

Science is not religion. It isn't a moral imperative that you follow science. Since you are limited by science every day in the real world (i.e. gravity is always getting you down), why let it limit your imagination?


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