Sternfinder
1
Star Finder (Celestial Globe)
1
Indicateur d’étoiles
Bedienungsanleitung
1
Operating Instructions
1
Mode d’emploi
© 2012 FPM Holding GmbH
23
4.1.3 T
HREE
-
DIMENSIONAL
R
EPRESENTATION OF
THE
S
OLAR
O
RBIT IN THE
C
HANGE OF THE
S
EASONS
Marking the sun’s position on the ecliptic for a certain date, one may, according
to item 5.1.2, watch the daily sun’s orbit for the geographic latitude set.
For determing the solar latitude at noon: Turn the star globe until the solar
position marking reaches the undivided southern half of the altitude circle.
Having loosened the knurled screws (12) and (13), turn the divided northern
half of the altitude circle to 12
h
, or 180°, of the horizontal circle without
changing the position of the star globe, set the location pin by shifting the star
detector to the solar position marked, and read off solar’s latitude on the
latitude circle from the index mark of the star detector.
Accordingly, the solar latitude may also be approximately determined for any
other time of the day.
Example 1:
5
= 54° N
June 21
December 21
Sunrise
3.20
8.40
Sunset
20.30
15.20
Solar latitude at noon
+ 60°
+ 14°
In the same way, the different solar arcs in extreme geographic latitudes may
be illustrated.
Example 2:
Singapore
5
= 2° N
June 21
December 21
Sunrise
4.30
7.30
Sunset
19.30
16.30
Solar latitude at noon
+ 111°
+ 65°
