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The authors don't say what the source of magnetism is, nor why the merger triggered it. Is it because of rotation, caused by the two stars spiralling in toward
by denton-scratch 3y ago
The authors don't say what the source of magnetism is, nor why the merger triggered it.
Is it because of rotation, caused by the two stars spiralling in towards each other?
But thinking about it, I don't know why a spinning blob of molten iron should result in a magnetic field; if there's magnetism, there should be electric current, and I don't know why a star merger should result in a current. In fact, apparently I don't know why either the Sun or the Earth has a magnetic field.
- pfdietz 3y agoIt's a common phenomenon in astrophysics for rotating objects to amplify seed magnetic fields, in something called "the magnetorotational instability". This is the source of strong magnetic fields in accretion disks that form jets from accreting black holes, neutron stars, and protoplanetary systems. https://en.wikipedia.org/wiki/Magnetorotational_instability https://en.wikipedia.org/wiki/Magnetorotational_instability
- denton-scratch 3y agoThanks - I only just realized I didn't understand this, when I thought about it. I'm rather gratified that the answer isn't simple and obvious; I didn't understand it because it's beyond my intellectual capacity, not because I'm ignorant, and I think that's an OK excuse.