trilithium
"I Wish I Knew"
Hi all, I am quite new and I hope you haven't discussed this topic already but here we go. A few years ago I watched a documentary titled "Earth's Magnetic Field" and it was quite interesting to say the least. They discussed how today the Earth's magnetic field is losing strength and has been for some time. To make it short-er, scientists dug down in the earth to reveal the layers with which they can study to reveal many things about the past. Subsequently, they found conclusive proof that the magnetic field used to be reversed ie:Magnetic south. I think they said it flip-flops periodically from magnetic north to south and has been doing this for a long time. I think they said the last time it happened was something like 700,000 yrs. ago. The field weakens when it's getting close (this is wide open for discussion) to flipping again. When they looked at a specific layer, they found all the particles in that layer positioned the exact opposite from the layers above it, and all the particles in the layers below that specific layer to be oriented the same as the specific layer, indicating a flip or flop of the magnetic field. Really interesting stuff I think, they also speculated that Mars once had a magnetic field, I don't think it has any now, thus had an atmosphere more like ours. After doing a search, I found this youtube video which I'm pretty sure is from the original documentary that I saw. I will try to include it here.
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