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Consider
the Sun’s daily motion at different times of the year
•At the Vernal Equinox Sun
is on the celestial equator.
•At the Autumnal Equinox
the Sun is also on the celestial equator.
•It rises due E, sets due
W
•It is up exactly 12
hours
•At the Summer solstice Sun
is a “northern” star.
•It rises N of E, sets N of
W
•It is up more than 12
hours
•At the Winter Solstice it
is a “southern” star
•It rises S of E, sets S of
W
•It is up less than 12
hours
Key point: Consider sun fixed at a given spot on ecliptic over the period of one day.
(From our Text:
Horizons, by Seeds)