By using as a hypothesis that Ca1-1 refers to September 20 (263) and that from there onwards time runs without interruption it follows that Cb8-6 will be at April 12 (112) - given that each year measures 365 days. Therefore Spica and Alcor at Cb8-6 should be in their nakshatra position:
569 (Cb8-6) - 365 = 204 (Ca8-5), but curiously 467 (April 12) - 365 = 102 (= 204 / 2). In the autumn nights of April were seen close to the Full Moon the right ascension days of the spring month October. We can summarize the possible nakshatra and heliacal positions of Spica and Alcor prior to Cb8-6, all of them on side a:
Next problem is how to define the nakshatra dates. With 12h at September 20 we ought to find 0h at the other side of the sky, but Ca1-1 could instead be at nakshatra day 1 (March 22) which I earlier have suggested. This in turn should make the difference between heliacal and nakshatra dates equal to 263 - 81 = 182 days (not 181 as I earlier have proposed as a possibility). It means Spica and Alcor will be at the other side of the sky compared to γ and δ Phoenicis in the night:
October 10 (283) + 182 - 365 = 100 (April 10). And April 11 (101) + 182 = 283 (October 283). It means Spica and Alcor in the night will be at the other end of the sky compared to Ksora (δ Cassiopeiai).
Polaris was the 10th and last Tahitian star pillar and here we will find Ana-nia (Pillar to Fish by) suitably in the night at the end of side a. 365 + 107 (April 17) = 472 is a number which corresponds to 16 * 29½ nights and October 16 is the Gregorian day before number 290 (= 10 * 29). | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
