The Orientations of the Giza pyramids and associated structures by Erin Nell and Clive Ruggles
The orientation of Menkaure's causeway is 0° 50´ North of East.
azimuth = 89° 10´
It seems to me that if this measurement is accurate, then it creates a problem. The notion that the Giza architects were off by a whole 50 degrees of a circle in relation to the ideal 90 degrees azimuth. Just take a look at the orientation error of Khufu pyramid's base, or even Menkaure's.
So, if I repeat these readings are correct, then I think I have found the solution to the Menkaure causeway design.
Let's station ourselves at the beginning of the Khafre causeway, just outside the mortuary temple.
We consider a flat - ideal horizon.
We will take into account light refraction.
I use Stellarium software.
Let's take one of the two dates of the years that the Sun aligns with the causeway. Here I will use the Fall alignment of this year.
rising Sun azimuth = 103° 26' 13" (the altitude of the center of the Sun disk is -0° 16' 4.8", half the phenomenal radius of the Sun)
The date is October 25 2018. The time this occurs is 06:03:44 UTC+02:00
So why is the Menkaure causeway azimuth - angle off by 50'?
It is simple.
We take the next day - October 26, 2018, and we fine tune the time of day so that the Sun has the exact same azimuth that it had the previous day(25th) when it aligned with the causeway.
The azimuth is 103° 26' 12.4" and the time is now 06:01:14 UTC+02:00
We look at the phenomenal altitude of the Sun. It is:
a = -0° 50' 48.3"
The Sun reaches it's culmination when it crosses the Meridian in the South. South is thus symbolically "up" and North is symbolically "down". As we can see above the altitude of the Sun is negative - below the horizon, therefore it relates to the North. This is the reason that the azimuth of the Menkaure pyramid causeway is 0° 50' North of East.
No equinox needed.
The same methodology holds for the spring date that the Sun aligns with the causeway. But this naturally works for the opposite direction - the Khufu causeway angle also.
Therefore instead of needing 6 dates each year, we actually need 4 dates.
Edited 2 time(s). Last edit at 27-May-18 02:50 by Spiros.