Michael;
Ok, let's make it easier.
On any day I want to stand in my backyard and look due east.
I don't want to travel anywhere.
Do I look at where the sun will rise on the equinox or do I look
slightly to the left of that? (northern hemisphere)
If you tell me to look slightly to the left of where the sun will rise
on the equinox it would mean two things:
1. the sun doesn't rise due east on the equinox
2. the east west line is not straight but curved
Thank you all for your replies.
brent
On 9/15/2015 4:00 PM, Michael Ossipoff wrote:
Hi Brent--
The paradox involves what you mean by "travel due east'.
If you travel due east, and keep on traveling due east at every point
of your journey, then you will indeed follow a parallel of latitude.
If you were to drive your car in that fashion, always going due east,
along a parallel of latitude, then your car's wheels and
steering-wheel would have to be adjusted for a (slight) left-turn.
...as, for example, if you wanted to drive east along the U.S-Canadian
border.
But there's another thing that you could mean by traveling due east:
But, if you set out due east, and then travel in a straight line,
without letting your car's wheels curve your car left or right at all,
then you're not following a parallel, and, you'd indeed end up going
farther and farther south from your original latitude.
As others have pointed out, a straight line on the Earth is also
called a "great circle".
So, the paradox was just the result of two different meanings of
"travel due-east".
Michael Ossipoff
On Tue, Sep 15, 2015 at 10:10 AM, Brent <[email protected]
<mailto:[email protected]>> wrote:
I'm confused maybe.
I live in the northern hemishpere and anticipating the equinox on
the 23rd.
Supposedly the sun will rise due east.
So if due east is a right angle from north south and I traveled
due east I would not follow my line of latitude.
I would get further and further south of my latitude the further I
traveled.
So either the lines of latitude are not east west lines or due
east is not a straight line but curved.
I suspect lines of latitude are not east west lines?
They would work fine if the earth was not tilted, but it is.
Wouldn't it make sense to coordinate the globe so lines of
latitude (or call them something else) are straight and a right angle
from north south?
brent
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