Say where the station being worked is

N1MM writes a line under its entry window with the beam heading, the heading the
long way round, the distance and the sun times at the other end. This writes the
same line.

SunTimes is the published sunrise equation, with the usual -0.833 degrees for
the sun's radius and refraction at the horizon, and it returns nothing on the
days inside the polar circles when the sun does not rise or set. It agrees with
published times for London at both solstices, Sydney in June and the equator at
the equinox, to within three minutes.

StationPath picks the position: the grid square when the contest exchanges one
and it has been copied, then the call history file, then the country file, which
puts the station in the middle of its country. That is close enough to point a
beam with. Our own end comes from the station grid square, or from the country
file for our own call.

One thing to know when reading the times: they are that station's own sunrise
and sunset in UTC, so for Japan the sun rises late the evening before.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -173,6 +173,18 @@ in again while you are running, and `EsmSendsCorrectedCall` sends the call again
 in front of the last message when you have corrected it — copy `SM3AB`, fix it
 to `SM3ABC`, and the key sends `SM3ABC TU DL1ABC`.
 
+### Where the other station is
+
+Under the entry window is the line N1MM writes there: the beam heading, the
+heading the long way round, the distance in kilometres, and the sunrise and
+sunset times at the other station.
+
+The position comes from the grid square when the contest exchanges one and it
+has been copied, or from the call history file, and from the country file
+otherwise, which puts the station in the middle of its country. Sunrise and
+sunset are worked out from that position for today; inside the polar circles the
+line says the sun does not rise or set.
+
 ### Editing the log
 
 Double-click a cell in the log window to change it. The columns follow the