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We took three 13 year-old girls on our family cruise yesterday, our daughter
and two of her friends.  Once anchored I went to the foredeck to shoot the
forenoon sun, escaping the crowds aft and below.  After I had completed my
sights, I called the kids up to see if they wanted to try the sextant.  They
all ran forward.

Only one of them had ever looked through the sextant before (my daughter,
once).  None had any prior sextant instruction.  I asked the first girl to
find the sun on the horizon (preset altitude).  She found it quickly.  I
showed her the index arm knob, so she could make the sun's image go up and
down.  Then I got her to bring the sun down to the horizon while one of the
other girls noted the time on my watch, attached to the sextant.  I wrote
down the time and sextant alitude.  Then I had her take two more sights, and
wrote those down too.

It soon became a competition.  Whithin minutes all 3 girls had each made a
round of 3 sights.  Kids learn quickly!  Being kids, however, they soon lost
interest and bolted off for more swimming, not the least interested in
waiting for the sun to hang at LAN.

When I averaged each girl's round of sights and reduced them on my Palm
handheld computer using CelestNav, their intercepts were 8, 6 and 0.2 miles
from our GPS position.  I was rather surprised by that, expecting much
worse.  The boat was rocking gently in a 5 knot wind, and we were using a
3.5 power telescope with a split-horizon mirror.

I still have not confessed to my daughter that her 3-sight 0.2 mile
intercept through her 13 year-old's eyes beat my 5-sight 0.6 mile result
through my 52 year-old eyes!!  Some day she'll find it in this archive, I
suppose.

Jim Thompson
jim2@jimthompson.net
www.jimthompson.net
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