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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)