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| First leg of our Northern Odyssey |
And tomorrow we’re away! First stop Seattle for a few days with friends then on to Nome, Alaska, where we will board a rather luxurious icebreaker and navigate across the top of the world seeking out the Geographic and Magnetic North Poles. Ours will be the first 'cruise' ship to attempt to reach the North Magnetic Pole so it is pretty exciting. This will be an exploratory voyage with 20 scientists on board. There is a rough itinerary but given that this is the first journey across the top of the world by a 'cruise' ship, anything could happen!
But first, indulge me a little as I share what excites me about the first part of our northerly voyage – to reach the two North Poles. And I promise to tell you about the journey itself as it unfolds.
Talk to me about poles! Physics 101, enter stage left – sort of. The earth has 3 axes, but I am not about to get into the nitty gritty of it all because I still have in my head the High School Open Day Science lab with its bar magnets and iron filings. However … Firstly there is the Earth’s rotational axis, and with it, the location of the Geographic North Pole that wobbles very slowly, like a spinning top. This wobble is called axial precession (all things in our universe vibrate but that is another story) and it takes the Earth's axis about 26,000 years to complete one circular wobble. ‘They’ say it is all to do with the redistribution of Earth’s mass as the crust has slowly rebounded after the end of the last ice age; maybe a redistribution of water? Whatever the cause, it seems we are always on the move.
And then there’s the North Magnetic Pole which is a spot on the surface of Earth's northern hemisphere at which the planet's magnetic field points vertically downward so if a magnetic compass needle were allowed to rotate in three dimensions (which mine can’t), it will point straight down. (An inclinometer – by any one of about six or seven names - is used for this.) There is only one location where this occurs – somewhere near but not necessarily/rarely if ever at the Geographic North Pole - they are driven by different forces. It gets more complicated when people refer to the Geomagnetic North Pole so I’m not going to go anywhere near talking about that. It seems to me rather more theoretical than measurable – without loads of complex physics. Thank goodness did you say?
The fascinating thing for me is that the North Magnetic pole (remember the iron filings?) has moved and continues to move, over time according to changes that occur in Earth's molten outer core. Unsurprisingly, its southern hemispheric counterpart is the South Magnetic Pole but that is not at a direct line through the earth. In case you are not aware, it was our Sir Douglas Mawson who on 16 January 1909 with two others on Shackleton’s Nimrod Expedition, was first to reach the South Magnetic Pole. (We will be travelling there at the end of next year when we visit Commonwealth Bay and Mawson's base). (LATER. Alas, this didn’t happen because we had to cancel that expedition, but we still hope to go there early in 2028.) A little aside, you might be interested to know that the invention of the magnetic compass is attributed to the ancient Chinese during the Han dynasty (202 BC - 220 AD).
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| The passage of the North Magnetic Pole since first recorded in 1831 |
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| Strengthening magnetic 'blobs' in the earth's molten outer core are pulling the North Magnetic Pole towards Siberia away from Canada |
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| And we have packed our compass for a bit of fun! |
Stay tuned as we navigate north and cross the top of the world from the Bering Straits to Longyearbyen, Svalbard. We will then be flown to Paris where we jump on a plane and head NW to the Faroe Islands and further ..... it will be an interesting tour map!
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