This got me thinking about how and why the ancients would build such things. It takes a lot of capital to build something like Stonehenge or the Pyramids at Giza. Such public works projects are only available to societies that are already commercially successful. Building infrastructure that is useful in launching global expeditions implies that a powerful civilization wants to go somewhere far away, on military expeditions or trade missions. Interestingly enough, Mr. Vahai's research indicates that the alignment of an ancient civilization's pyramids correlates with whether it was primarily a commercial power or a military power. His research also implies that some pyramids may have doubled as public works projects that could pump water (pending confirmation with more research). That is potentially a breakthrough observation, and it actually makes sense that a civilization good at building things to enable global expansion would find multiple uses for these structures.
A civilization that can project power beyond its borders is a global power and a force for changing human civilization. The U.S. military uses GPS to coordinate air strikes and photo reconnaissance missions far from its shores. Knowing where you are and where you're going is indispensable for success. The ancients figured that out long before we came along. It took the rest of us thousands of years to catch up.