3 ms·

True north doesn’t change - magnetic north does.

• pavlov 7y ago
  Ah, that’s my confusion. Thanks!
• dragonwriter 7y ago
  > True north doesn’t change The alignment of a structure fixed to the ground, relative to true north, will change over time, because the while the axis of the earth can be viewed as fixed, the land on the Earth is not fixed with respect to that axis, but moves.
  • nitrogen 7y ago
    The axis isn't strictly fixed; it shifts as the plates etc. shift.
  • bananabreakfast 7y ago
    Not really. The time scale for large movement is much larger than thousands of years. Since the great pyramid was build 4500 years ago the mid atlantic ridge has only moved about 100m. That's just lateral translation, most of which probably did not end up moving egypt much anyway and definitely not enough to throw off the direction a pyramid is pointing by more than a second or two.