Tuesday, February 22, 2022

Cosmic Places and Sacred Landscapes

 Weeks 3 and 4 of my "Discover the Ancient Sky" class covered wandering planets, key stars and constellations, and huge sites that represented sacred landscapes that are far more than solar and lunar observatories.


Links to Key Sites and Monuments:



Links to cultural stuff:

How to read the Maya Calendar

Inca astronomy in South America. Also here.

Videos seen in class:





Additional Bibliography:

Aubrey Burl (2005)  Prehistoric Astronomy and Ritual

J. L. Heilbron (2001) The Sun in the Church: Cathedrals as Solar Observatories

University of Maryland Archaeoastronomy center

UNESCO portal: Portal to the Heritage of Astronomy

Astronomical links: 

Stanford University Solar Center

Monday, February 14, 2022

Our Wonky Moon and Lunar Alignments

 Last week we continued with solar alignments at sites like Chankillo, Peru (see this wonderful video) and spent some time on the lunar orbit. Because the moon's orbital cycle is 18.6 years to repeat its tilting pattern, it is very hard to visualize. The best explanation I have found is here, at the University of Massachusetts Sunwheel website (a sort of mini-Stonehenge created by Prof. Judith Young).

            Thirteen towers at Chankillo. Source: photo by David Edgar, Wikipedia

Another wonderful reference is "Ancient Observatories," by Deborah Scherrer at the Solar Center at Stanford University.

Thursday, February 3, 2022

Why study ancient stargazers?

 During the month of February 2022, I'm teaching an Olli course on Discovering the Ancient Sky: The Archaeology of Astronomy.

Why study ancient stargazers? Because people discovered thousands of years ago that being able to predict celestial events such as eclipses of the sun or the flooding of major rivers gave them control over human resources and human behavior. How much of early astrology and astronomy is based on observation vs. mathematics? We owe a considerable debt to ancient Babylonia and Egypt for their accurate observations and timekeeping and to Greek philosophers for their views of the cosmos. However, what people were able to observe depends on several things: time of year and season (controlled by the earth’s movement around the sun and the earth’s tilt), and latitude. How ancient sites were oriented depended on what various cultures considered important (e.g. direction of Nile flow and rising of the sun in Egypt vs. Cahokia’s lunar and Milky Way alignments).

I consulted many books and websites to prepare for this class. Here are some of my favorites: 

 *Taylor, Ken. Celestial Geometry: Understanding the Meanings of Ancient Sites (2012).

*Hadingham, Evan. Early Man and the Cosmos (1984).

*Cornell, James. The First Stargazers: An Introduction to the Origins of Astronomy (1981).

*Aveni, Anthony. People and the Sky: Our Ancestors and the Cosmos (2008).

Aveni, Anthony. Stairways to the Stars: Skywatching in Three Great Ancient Cultures (1997).

Moche, Dinah L. Astronomy: A Self-teaching Guide, 8th Edition (2015).

Marshak, Stephen and Robert Rauber. Earth Science: The Earth, the Atmosphere, and Space, especially Part 5: “Our Solar System and Beyond” (2020 edition).

For a video on the earth's tilt and how that affects the seasons, go here.

For the video on New Grange, Ireland that I showed during the first class, go here.