Here is the evening sky scene for Thursday evening, October 19.
My previous post was bungled – blame it on the frustrations of typing with a bandaged right hand. I said what I wanted to say about the wild pet trade, but something caused the opening sky scene to drop out. I corrected this later (http://www.universalworkshop.com/2017/10/15/serpents/), but later is too late.
But we could look again at Serpens, the snake constellation that now wriggles above the western horizon, and that is divided into two non-contiguous parts. The only geographical analogy I can think of is the county of Flint, at the northeast corner of Wales. It has a larger piece and a smaller piece, separated by the county of Denbigh. At least this was so until the boundary “reforms” of the 1970s and onward, which thoroughly messed up the traditional counties of Britain. I think there was also an outlying bit of Warwickshire enclosed in Worcestershire, and, at some earlier time, a droplet of Dorset isolated in Devon. Probably there were other such instances in the incredibly complex map of the Holy Roman Empire. Elsewhere in the world, there is the African country of Equatorial Guinea, divided into a mainland part and two islands, which are themselves separated by another country of two islands (Sao Tome and Principe); and Malaysia, also separated into pieces by water; but that isn’t really the same as being separated only by land. A land situation that didn’t persist in reality was the 1947 United Nations partition plan for Palestine, in which the three areas left to the Palestinians, Galilee, the West Bank, and Gaza, touched at two points, like squares on a checkerboard.
Serpens in sky pictures is a snake reaching across the middle of Ophiuchus, who holds him; but in a map with boundaries, the stars had to be assigned to either the man or the snake, and they were assigned to the man. Otherwise, we might have had a three-way divided constellation: Ophiuchus’s torso, his right leg, and his left.
The two parts of Serpens are commonly called Serpens Cauda and Serpens Caput. I – pedantically, if you like – balk at this because you can’t slap nominative nouns together like that in Latin; grammatical would be Serpentis Cauda and Serpentis Caput, “tail of the serpent” and “head of the serpent.” My compromise is Serpens (Cauda) and Serpens (Caput).
The two parts are treated as one constellation in that there is only one sequence of Greek letters for the main stars in them. The stars are called Alpha Serpentis (not Alpha Capitis, or Alpha Serpentis Capitis), etc.
Another, much larger constellation, Argo, was divided into parts, though the parts touch: Carina, Puppis, and Vela, the keel, poop, and sails of the ship. As with Serpens, they have only one sequence of Greek letters; yet, unlike Serpens, the three parts are treated as separate constellations, in that the stars are called Alpha Carinae, Gamma Velorum, etc. – not Alpha Argous etc.
(I see that that’s a whole lot of puzzlingly different kinds of genitive endings: -is, -ae, -orum, -ous. You won’t believe me, but Greek and Latin grammar are fun!)
You probably know that herpetology is the study of reptiles, from the Greek herpein, “to creep,” cognate with Latin serpere – an instance of a frequent correspondence between the cousin languages, as in their words for “six” and “seven”: sex, septem; hex, hepta.