figuring out how the universe works
The ancient roots of astronomy
By PIERRE PAQUETTE
Royal Astronomical Society of Canada
In many cases , what may have seemed very complex and complicated for our ancestors seems to us obvious or simple — sometimes , maybe even too much , to the point that we forget how we got to learn those facts . Many examples are to be found in astronomy . Join me in this series of articles in which we ’ ll explore the path of history and review how the monument of astronomical knowledge was built for us by the people of the past .
Moonwatcher ’ s Heirs The movie “ 2001 : A Space Odyssey ” opens with a short subplot of tribes of apes fighting for access to a waterpoint in what seems to be a rocky desert . The novelization of the movie introduces us to one of these apes , called “ Moonwatcher ” by its author , Arthur C . Clarke . It is quickly understood that Moonwatcher ’ s tribe eventually becomes the ancestor to all Humankind , while the other tribe either dies out or remains simian . While it is impossible to know what went through the heads of protohumans or early humans , it is likely that they did actually “ watch the Moon ,” as the cycle of our natural satellite brings its succession of brighter or darker nights , depending on its visible phase . This , in a sense , represents the very beginning of astronomy : A simple curiosity for what is up there in the sky . It probably didn ’ t take long to keen observers to realize that some of the “ stars ” seem to move — the Greeks later would call those πλάνητες ἀστέρες planētes asteres , or “ wandering stars ,” which eventually became the modern English word “ planet .” And while the other stars would remain stationary in relation to each other , they would gradually shift from one night to the next — another early realization was that they would eventually come back after a year . This established the notion that celestial phenomena — at least some of them — were connected to our earthly existence . Not knowing , back then , that the Earth is but a planet moving through space like the others , our ancestors thought that the Sun , the Moon , planets , and stars may be the cause of changes down here — a thought that survives to this very day in the form of astrology , but which was completely disproved by modern science . Mind you , there is a connection , but not that kind of connection ! But this is a story for another day . The sky became a calendar to early civilizations . This is attested in some of the lore associated with some constellations — groupings of stars which seem to draw
COURTESY OF User Fæ on Wikimedia Commons
The Venus tablet of Ammi-Ṣaduqa , dating from the 7th century BCE , records the appearance of the planet Venus in the skies over Babylon around the years 1700 to 1500 BCE . It is written in cuneiform , the oldest writing system which has survived to this day . The dimensions of the tablet are 17.14 cm × 9.2 cm × 2.22 cm .
persons , animals , mythological creatures , or objects in the sky . For example , a specific bright star was seen to rise just before sunrise in the spring , and to set just before sunset in the fall . To early agricultural societies ( ca . 7500 BCE ), it thus became associated with the times of sowing and of reaping . Soon after writing was invented , texts report that it and the surrounding stars were called the Furrow — the trench cut by the plough in the soil to plant seeds in . We now know
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