<HTML>Okay, folks, here's a view looking south from Giza in 10430 BC, the low point of Zeta Orionis (Alnitak) in the precessional cycle. The screenshot is from Skychart III. Orion is in the centre. Aldebarab and the Pleiades are to the upper right, and the bright star in thelower centre left is Procyon.
Click on this for a proper, larger view.
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Fair enough you might say, Orion is sitting nicely on the horizon, like GH &RB say (Incidentally, the positions of the stars in Orion are actually about 2 degrees lower in the sky than given in KoG(MofS).
<B>But they forget to factor in Atmospheric Extinction into their calculations</B>. Saiph, the bottom left hand corner star of Orion is so low in the sky that it is not visible with the naked eye between <B>11600 BC</B> and <B>9600 BC</A>.
Here is a simulated view of what the sky actually would look like, with atmospheric extinction included:
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The lowest visible star is Rigel (normally the brightest star in Orion), but as it is so low, it is only mag 4.2, i.e not very impressive at all. Even the belt stars, 9-11 degrees up are dimmed by about a magnitude...
So the question that springs to my mind is - if RB &GB are correct, then why would the Egyptians use a constellation that would would only have been half visible for the previous millenia?
Now, if you'll excuse the flight of fancy, Sirius becomes visible at about 10400 BC for the first time since 12500 BC, but it doesn't become prominent until about 9600 BC...
So both Orion and Sirius are completely visible at 9600 BC, surely this would be a better occasion to mark?
Best Regards,
Dave</HTML>
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