Here's the update I promised in my post on the Dendera Zodiac. If you remember, the zodiac is an ancient Egyptian bas-relief carved onto huge sandstone blocks. It originally formed part of the ceiling of a temple in Dendera, Egypt, but is now on display in the Louvre in Paris.
The design is a representation of the sky. Egyptologist Sylvie Cauville and astrophysicist Eric Aubourg used the positions of the star constellations and planets to date the Zodiac to between 15 June and 15 August in the year 50 BC, during the period between the death of Cleopatra's father, Ptolemy Auletes, in 51 BC, and the establishment of joint rule between Cleopatra and Caesarion (her 5-year-old son by Julius Caesar), in 42 BC.
Two eclipses - the solar eclipse of 7 March 51 and the lunar eclipse of 25 September 52 - are represented on the skyscape in the locations where they would have occurred.
But why would the Egyptians have wanted to commemorate this particular moment? I emailed Cauville and she says her hypothesis is that the total solar eclipse coincided in Alexandria with the death of Cleopatra's father. "She [Cleopatra] may have wanted to inscribe for eternity the passing of power from King-Rê to herself, the female sun."
I'm so glad I asked! Rê is another name for the sun god, Ra, by the way. The pharaohs, including those of Cleopatra's dynasty, often claimed that they were sons and daughters of Ra.
Dendera would have been chosen because the temple there was dedicated to female royalty. (The temple at Edfu, where two similar zodiacs are located, is dedicated to the male royalty.) The Dendera zodiac was on the ceiling of one of the temple's two chapels dedicated to Osiris, the god of eternal return. There's more about all this in Cauville's 1997 book, Le Zodiaque d'Osiris.
"It's a shame that so many fanciful things have been written about the Zodiac," adds Cauville. "The astronomical reality is so much more beautiful." Couldn't agree more.
[Cauville's comments have been translated from French]