The annual path of the Sun across the celestial sphere is marked on the rete by the outer edge of a circular band on which the positions of the zodiacal constellations
are marked out.
A line drawn from Rigel northeastward through Betelgeuse points to Gemini, the Twins, another fine zodiacal constellation.
The Dipper's Handle curves southward toward two bright stars in the eastern half of the spring sky: zero-magnitude Arcturus in kite-shaped Bootes, the Herdsman, and 1st-magnitude Spica in the sprawling zodiacal constellation Virgo, the Virgin.
The first statement is concerned with a partially visible zodiacal constellation--an occurrence which possibly stands for incompleteness, if MAS-su ("its half") indeed refers to lumasu, the zodiacal constellation.
Why is this zodiacal constellation relevant for the animals?
Cancer, the only fainter zodiacal constellation
, won't appear for several more months.
I contended that the first quartet of zodiacal constellations were created to improve the solar calendar.
The recent book by Ryan and Pitman adds support to these considerations and the astronomical dating of the first zodiacal constellations.
Or I'll mention that every year the Sun drifts through the 12 common zodiacal constellations
lying along its path in the sky (the ecliptic).
In "When the Zodiac Climbed into the Sky" (S&T: October 1995, page 28) I demonstrated that the age of the zodiacal constellations
could be determined using this concept; here I propose that the idea can be taken a step further.
It's outside the zodiacal constellations
, a rare occurrence, perched in a corner of Cetus near Pisces according to how the constellation borders are drawn today.
At the beginning of the 19th century Pierre-Simon de Laplace, in his Exposition du Systeme du Monde, declared: "The names of the zodiacal constellations
were not haphazard fancies.