Okay, if I was confused before, I'm really confused now
I guess I understand in basics what latitude and longitude are, but I imagine the difference between one degree on either of them is huge. If I'm correct, there is 90 degrees north and south of the equator for latitude and 180 degrees left and right of the Prime Meridian (for a total of 360 degrees) for longitude. How much space is between each line of lat. and long. ? Miles or km?
Then, if I read correctly, Trevor use the astrolabe to pinpoint his longitude and used the compass to measure his direction and guessed his speed. Now he did this during the day with the sun, as well as at night using the southern cross (is that the actual geographical south, or is it off like Polaris), do both readings tell him the same thing? Then I seem to recall their is geographical north, magnetic north and true north. I'm sooooo confused and I'm in the wrong hemisphere .
Does the astrolabe replace the sextant? If so, is it a simpler version of the latter?
Usually when someone talks about geographic position I skip over it, because I just don't understand it. I am curious though since this seems to be a major part of the story.
Trevor's life depends on me understanding it
Help!!!