John Carmichael writes:

> We could make this question even more complimented if we consider the speed
> of light.  When we see the sun's center on the horizon we are seeing light
> that left the sun about 8 minutes earlier.  The sun really has already set.
> (of course this has no practical effect on sundial time, but is fun to think
> about!)

What does that mean, "The sun really has already set."?  I would say,
"By the time the light now leaving the sun gets here, I will have
moved behind the edge of the Earth."  But the sun really is located in
the direction from which the light I see is coming.  (There's a teeny
tiny shift in the direction if I am moving perpendicular to the line
of sight, but that is not the case at sunset.)

Art Carlson

Reply via email to