O: "Gantenbrink’s survey yields a 32.602 degrees angle for the North GP King’s Chamber slope, not 31.2 degrees as you state."


From Gantenbrink's survey on his web site: "The "Mankiller" tunnel is accessible from the outside of the Pyramid, so we could manually measure the angle of shaft inclination through this section. The average angle is 31.20°, determined by 5 measurements made over a length of 11 m." (11 m is 36 feet)


This is the angle I am using, because it tells us what area of the sky the top outlet of the north shaft is actually facing.

I use StarChart III set to highest precision that takes into account precession, proper motion, nutation etc., set to latitude for Khufu's pyramid, and 60 m elev. - Thuban is ~31.2 degs alt. at upper culmination, c.2570 BC

The top outlet of south shaft is facing an area of the southern sky ~45 degs above the horizon - Alnilam the centre star in the 3-star asterism in the centre of Orion was ~45 degs alt. c.2570 BC.


The underlying design scheme of the upper shafts is based on sqd 7 (45 degs) for the south shaft, and sqd 11 (32.47 degs) for the north shaft. However, the top 11m (36ft) section of the north shaft has a shallower angle of incline of 31.2 degs, so this is the angle that defines what area of the sky the top outlet of the shaft is actually facing.

CT



Edited 1 time(s). Last edit at 11/27/2009 06:27PM by Chris Tedder.