Cosmic magnetic fields

The mention of cosmic-scale magnetic fields is still likely to met with an uncomfortable silence in some astronomical circles – and after a bit of foot-shuffling and throat-clearing, the discussion will be moved on to safer topics. But look, they’re out there. They probably do play a role in galaxy evolution, if not galaxy formation – and are certainly a feature of the interstellar medium and the intergalactic medium. 
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At the stellar level, magnetic fields play a key role in star formation, by enabling a protostar to unload angular momentum. Essentially, the protostar’s spin is slowed by magnetic drag against the surrounding accretion disk – which allows the protostar to keep drawing in more mass without spinning itself apart.  At the galactic level, accretion disks around stellar-sized black holes create jets that inject hot ionised material into the interstellar medium – while central supermassive black holes may create jets that inject such material into the intergalactic medium.   link