There was a time when everybody knew the stars
For stars were used by everyone in measuring the time –
Startracks marked the passage of the hours in the night
Heliacal risings and settings of sentinel stars marked the seasons
The stars are nighttime guides for travelers, at sea or on the land
Any traveler would know the movements of sun, and moon and stars
Everybody knows the stars, and talks about the stars
But to speak about the stars, we must agree upon their names
We speak of a time some centuries before the alpha-beta
History resided in the memories and stories
of the people of a village, of a city, of a kingdom.
Things remembered by only a few are forgotten in a generation or two,
But things that are known to everybody tend to be remembered.
Everybody knows the stars, so
The names of the stars are resistant to change –
That’s the point we’re getting at. Put another way,
The constellations were culturally ‘sticky’ back in the day
* * * * * * * * *
By accident of history, modern astronomers identify regions of the northern sky per the listings in Ptolemy’s Star Catalogue (Almagest VII.v – VIII.i.) The astronomers of ancient Greece cobbled together a creole sky, drawing from Mesopotamian, Mediterranean and Ægean traditions, which came to be an international standard.
Egypt had its own traditions of astronomy and astrology, which were not adopted by many outside the Nile valley. The Minoans must have developed their own traditions of astronomy, of which we know little. Separate traditions evolved in China, northern Africa, the Americas, central Africa, the Pacific islands, southern Africa, Australia, the Arctic, and everywhere; these aren’t addressed here.
To understand the origins of the modern northern sky, we’ll consider how the people of Mesopotamia and the Mediterranean used the stars, from the late Bronze age (before the alphabet), into the Iron Age and written records – roughly from 1500 BCE to 150 CE.
The stars of particular parts of the sky were put to different purposes:
Northern stars, which never set, were used to mark direction, and to track the time at night
Bright stars of central latitudes marked the cycle of the year by their heliacal rising and setting The zodiac, through which the planets, moon, and sun move, was important to astrologers
Let’s look at these in turn.
Stars of a Sailor
We propose that the northern Greek stars were standardized by sailors of the Mediterranean/AEgean.
This argument is rooted in two assumptions.
First: We presume that sailors used the stars extensively for navigation and timekeeping. There may have been regional differences in how the stars were grouped and named, but all could read the motions of the circumpolar stars. Due to the earth’s slow precession, the apparent axis of rotation of the heavenly sphere, which passes near Polaris today, was somewhere in the coils of Draco four thousand years ago. Then, as now, most would have marked ‘north’ as the place about which the Seven revolve.
The seven stars of the septentrio are the most striking asterism of the polar sky. While they form the haunch and tail of the Great Bear, these seven are frequently cited in isolation as the Plough, the Wagon, or the Dipper. The Plough, we presume, derives from Anatolian tradition – for who would see a plough in the sky but a people familiar with ploughs? In the same way, the Wagon is a figure visible only to people familiar with horses and wheels, such as the PIE-speaking peoples who radiated from the eastern steppes. A dipper might have been familiar to peoples of many cultures, but was perhaps especially significant to sailors, as any ship spending a day or more between ports would have carried a barrel of fresh water – and a dipper with which to draw from it.
Second: We presume that then, as now, port cities were places where cultures mixed. Merchant ships from all around the AEgean and Mediterranean visited dozens of minor ports, across the islands of the Cyclades and the western Anatolian coast, to the major ports of the east Mediterranean coast, from Phoenicia to Joppa – places where sea-borne traders could meet with overland merchants from Mesopotamia and Sinai and Egypt. In such a setting, cross-cultural exposure and exchange can lead to creole dialects, fusion cuisines, and theological cacophany.
It seems fair to presume that a particular set of stars became a standard, shared by a polyglot collection of sailors. Agreement upon a set of northern constellations and sentinel stars was important for the members of a nautical crew. This was not the work of a committee, but the organic result of what seems, looking back, an obvious cultural necessity.
Heliacal stars
The heliacal risings or settings of especially bright stars were used to mark the passage of the year, by marking the heliacal rising or setting of various sentinel stars. For example, when the bright star Spica (the stalk of corn in the hand of Virgo) appears on the eastern horizon just after sunset, it’s time to plant the grain; when Spica appears on the western horizon just after sunset, only to quickly drop below the horizon, then it’s time to harvest the grain. [This is presented as an hypothetical illustration.]
Only the brightest of stars could be used for this purpose. The ancient Greeks didn’t name many individual stars; many of those they did might could been used for tracking the seasons of the year, and the hour of the night.
We suspect that the use of stars to mark times to plant and harvest may have spread from Anatolia, along with early agricultural practices. In a hunter-gatherer culture, the pace of life was driven by lunar cycles; the annual drift of the sun and the seasons was important, but the monthly cycle from new to full to new again was a critical pulse of time for animal life. With the advent of agriculture, adherance to a solar cycle became the focus of human societies. The heliacal rising and setting of particular sentinel stars was a very accurate tool for tracking the passing of the year.
Our choice of Spica as exemplar is not random.
Ptolemy gives names to two stars in the constellation Virgo.
One is the brightest star in the region (first magnitude), which Ptolemy calls ‘the star in the left hand called Spica’. In figures, Spica is typically depicted as a stalk of grain, and Virgo is often described as a corn goddess.
The other is a bright third magnitude star to the northwest, called Vindemiatrix. As its name suggests, its heliacal setting was tied to the harvest season for grapes.
Stars of the Zodiac
The stars of the zodiac were the first international scientific standard.
The peoples of Mesopotamia were farmers, using Anatolian-derived crops and methods. They had their own collection of constellations, many of them suggesting an agricultural society. For example, the four we know as the Great Square of Pegasus were called The Field; a hunter-gatherer wouldn’t immediately associate a square with a stretch of even ground, but a farmer in a village working a plot of land could easily see a square field.
With time, villages grew into cities, with rulers and councils and overseers and palaces and kings. Now, wherever there are palaces and kings and such, there are many attendants and hangers-on, various lickspittles and shamans and courtesans and scholars. The details are sketchy, but around four thousand years ago, shamans of the palace centers took an interest in the movements of the planets. Mars and Jupiter and Venus were easily found; Mercury and Saturn would only have been noticed by dedicated skywatchers.
A challenge faced by the earliest astronomers: how to describe the motions of the planets through the skies? Before the invention of longitude and latitude (and instruments to measure them), astronomers described the positions of the planets relative to the surrounding stars.
To that end, early astrologers created a map of the sky. In particular, a detailed map of the stars in that swath of the sky through which the planets moved. The stars of the Zodiac.
Though we define the stars today by longitude and latitude, the earliest maps of the sky were defined by star alignments. [See String Theory]
Using star alignments, one might report that ‘Mars was just west of the midpoint of the line between the crab’s southern claw and the second of three in the neck of the lion’, and other astrologers would be able to visualize. [Link to Memory Palaces]
A survey of pictographic images from ancient Mesopotamia suggests that the Zodiac has origins more than four thousand years ago. Very early images which scholars associate with the sky include images of scorpions, lions and bulls. Over time, a dozen figures were defined for this band of stars.
The starlines of Almagest VII.i take us twice around the zodiac, marking the lines
which mark the stars of the figures in the sky [LINK].
If you’re interested in a deep dive into the stars of the Zodiac,
and how these figures could have been defined before longitude and latitude,
take a look.
For more on the history of Mesopotamian and Mediterranian constellations, check out the work of J.H. Rogers [LINK].