Africa Astronomy: The Dogon Mystery
INTRODUCING THE SIRIUS STAR SYSTEM
Sirius is a star system and the brightest star in the Earth’s night sky. It is about 8.7 light years from Earth. It is a binary system of two stars – a white star, Sirius A, and a faint white dwarf companion star, Sirius B. Sirius B cannot be seen with the naked eye, and astronomers first guessed at its existence in the 1830s. It was first photographed in 1970 by astronomers using a very large (and very expensive! ) telescope.
Sirius - The Brightest
THE DOGON AND THE SIRIUS STARS
Way back in the 1930’s a pair of French anthropologists named Marcel Griaule and Germain Dieterlen spent many years in a remote West African village with the Dogon, learning about their amazing, mysterious astronomical knowledge. They were completely astonished that these Africans knew so much about celestial things without the use of sophisticated and expensive equipment.
Germain Dieterlen
Marcel Dieterlen and a Dogon priest
The Dogon believe that the brightest star in the sky, Sirius (what they call sigi tolo or "star of the Sigui"), has two companion stars, pō tolo (the Digitaria star or Sirius B), and ęmmę ya tolo, (the female Sorghum star or Sirius A).
Two Dogon sages Ongoulou and Innekouzou who met Germaine and Marcel
Sirius, in the Dogon system, formed one of the foci for the orbit of a tiny star, the companionate Digitaria star. When Digitaria is closest to Sirius, that star brightens: when it is farthest from Sirius, it gives off a twinkling effect that suggests to the observer several stars. The orbit cycle takes 50 years and they traced it through the year 1950 – exactly matching what Western observatories produced. They knew the length of its orbit in years, the shape of its orbit and the fact that the white dwarf is quite dense.
How the Dogon depict the Sirius system
Paths of Sirius A and B - Dogon sand drawing compared to that from Western observatory equipment
Orbit of Sirius B - Dogon diagram compared to Western.
ADVANCED KNOWLEDGE OF THE CONSTELLATIONS
Apart from the Sirius system, the Dogon have a huge wealth of knowledge of the constellations, stars, planets orbiting the sun, four moons of Jupiter, rings of Saturn and the Milky Way. All these and more through many hours of observing the night sky with their naked eyes!
Next time, we will continue discussing what other ancient African peoples know about astronomy.