The origin of magnetic fields in galaxies is still a mystery to astronomers. Popular theories suggest continual strengthening over billions of years. The latest results from Simon Lilly's group, however, contradict this assumption and reveal that young galaxies also have strong magnetic fields.
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What equates to the magnetic field of perigee galaxies for quasars that are billions of light years away (large: "whirlpool" galaxy; small: quasar OC-65)?
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"There is an astronomer joke that goes 'to understand the universe, we examine galaxies for radiation, gases, temperatures, chemical constitution and much more. Anything we can't explain after that we attribute to the magnetic fields'", explains Simon Lilly, Professor at the Institute of Astronomy at ETH Zurich. The creations of the magnetic fields in galaxies remain a badly researched mystery. Until now, it was deduced that galaxies which formed after the Big Bang 13.8 billion years ago had very weak magnetic fields that then proceeded to grow exponentially in strength over several billions of years. At least that is what the dynamo theory (see box), which is often used to explain the development of magnetic fields, conveys.
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