A 26,000-year astronomical monument hidden in plain sight (2019) (longnow.org)

Article summary

The Hoover Dam has a little-known monument on its western flank, a celestial map on the terrazzo floor of Monument Plaza, which marks the time of the dam's creation based on the 25,772-year axial precession of the earth. The monument was designed by Oskar J.W. Hansen and was commissioned by the US Bureau of Reclamation in 1931. The plaza's design is based on the earth's axial precession, which is the slow wobble of the earth's axis over a period of approximately 26,000 years. The monument is a unique example of a long-term thinking and astronomical knowledge being incorporated into a public work of art.

Main themes

• Astronomical monuments
• Long-term thinking
• Axial precession
• Hoover Dam history
• Celestial navigation
• Public art and architecture

What commenters say

• The monument is an example of an attempt to encode a date for distant future generations to understand, using astronomical knowledge and symbolism.
• The use of leading zeros in the year, as seen in the article's date format, is a whimsical attempt to give the reader a pause to think about long time periods, but others find it arbitrary and unnecessary.
• The demolition of the star map due to a drainage issue and contract dispute is a tragic loss of a unique piece of history and a crime against humanity.
• The reconstruction of the star map is underway, with some parts being remade and others being restored, and the project is expected to be completed in the near future.
• The monument's design and significance are not well-known, even among those who have visited the Hoover Dam, and its importance is only appreciated by a few who understand its astronomical and historical context.
• The article's discussion of the monument's design and history is fascinating and has inspired some readers to learn more about astronomy and the history of the Hoover Dam.
• The use of astronomical knowledge and symbolism in public art and architecture is a valuable way to promote long-term thinking and appreciation for the natural world.
• The preservation of historical monuments and public art is crucial for maintaining a connection to the past and understanding the cultural and historical context of a given time period.