Percision on the Pyramids

The three main Pyramids of Egypt at Giza are arranged in close proximity to each other, and Bauval was curious about the apparent lack of symmetry or geometry in their layout. He knew that there had to be some reason for why they were aligned in the way that is now seen overhead. inspiration finally struck as he looked up at the constellation of Orion, which has three main stars that form the middle section, referred to as the "belt." He realized that the Pyramids of Giza were configured in precisely the same manner as the "belt" of Orion, and he quickly proved his point by overlaying the site maps of the Pyramids and the star maps of Orion's belt on top of each other. Not only was each Pyramid in the proper position, but even the relative sizes and colors of the Pyramids were directly proportional to the magnitudes and colors of the stars in Orion's belt. (The Cheops and Khefren pyramids were both originally covered in white limestone and are approximately the same size, like the two main stars in Orion’s belt, whereas the Menkaure pyramid is significantly smaller and was originally encased in red granite, just like the dimmer and redder third star.)
As Bauval continued to investigate the matter, he realized that the architects of Giza had created a perfect duplication of the starry heavens on Earth – an idea that fit in perfectly with their concept of the connection between the physical world and the Duat, or spiritual world. Furthermore, the position of the Nile River relative to the Pyramids was identical to the position of the Milky Way relative to Orion's belt in the starry night sky. Further Pyramids near Giza seemed to suggest that several other significant stars of Orion and the nearby Hyades constellation were immortalized in stone on the Earth as well.
Figure 2.1 – Robert Bauval's Comparison of Orion/Milky Way with Giza/Nile Though this alignment is intriguing, it does not appear to give us any new information about the time that the pyramids were built. However, by using a program known as Skyglobe, Bauval realized that the only "recent" time that the Milky Way would be perfectly aligned with the Nile River was roughly 12,500 years ago. At that time, and only at that time, (unless you were willing to travel back more than 30,000 years ago,) one could stand on Earth and observe the Pyramids and Nile River at a distance, and watch the Nile align directly with the Milky Way, while the stars of Orion's belt would perfectly align with the positions of the terrestrial pyramids. This is caused by the phenomenon of the Earth’s precession, a long-term wobble in its rotational path that we will discuss later.
As a simple, preliminary explanation of precession, you would normally expect that when you get to the same time each year, where the Earth is at a specific angle to the Sun, such as the equinox or solstice, then all the stars should be in the same positions from year to year on that date. Nevertheless, the stars in the night sky will drift from those visible positions by one degree every 72 years, tracing a full circular path through an area of the night sky about every 25,920 years. If you build a temple to align with a star at the solstice time, then within a relatively short time your descendants would realize that something was causing these star positions to shift out of their previous alignment.