1. With star pillars I mean a limited number of prominent stars listed as a group, for instance those chosen by Chaucer for instructing his son in the use of the astrolabe: ... Little Lewis my son, I perceive well by certain evidences thine ability to learn sciences touching numbers and proportions; and as well consider I thy constant prayer in special to learn the treatise of the Astrolabe. Than for as much as a philosopher saith, 'He wrappth him in his friend, that condescendth to the rightful prayers of his friend', therefore have I given thee a suffisant Astrolabe as for our horizons, compounded after the latitude of Oxford; upon which, by means of this little treatise, I purpose to teach thee a certain number of conclusions pertaining to the same instrument ...
Except Alrediph they all are easily visible. "From its neighborhood radiate the Cepheid meteors, visible from the 10th to the 28th of June." (Allen) ... The term cepheid originates from Delta Cephei in the constellation Cepheus, the first star of this type identified, by John Goodricke in 1784 ... Classical Cepheids (also known as Population I Cepheids, Type I Cepheids, or Delta Cephei variables) undergo pulsations with very regular periods on the order of days to months ... "It varies between 3.5m and 4.4m over a period of 5 days and 9 hours." (Wikipedia) Surely the ancients must have noticed this phenomenon much earlier than John Goodricke ...
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