NavList:

   

Reply

Frank wrote-

"You shoot the Moon's altitude, then the Sun's, then three or five lunar
distances (noting only the time of the middle observation), then the Sun's
altitude, then the Moon's altitude. You average the two Moon altitudes,
average the two Sun altitudes, and average all the lunars. The observations
are then equivalent to a single simultaneous set at the middle time. Since
the altitude of the Moon matters least, you shoot it first and last. "

I don't understand. Except at very low Sun altitudes, the Moon correction
for (parallax and refraction) is almost always far bigger that that for the
Sun, which is mostly just refraction.

So I would change Frank's suggested order to Sun-Moon-lunars-Moon-Sun.

George.

contact George Huxtable, at  george@hux.me.uk
or at +44 1865 820222 (from UK, 01865 820222)
or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.

   

Reply