Archaeoastronomy

Equinox Observations at Atlatl Rock

Valley of Fire State Park, NV, USA

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Eine Zusammenfassung der hier berichteten Beobachtungen und deren Ergebnissen ist in deutscher Sprache verfügbar!

Welcome To My Atlatl Rock Web Pages!

When travelling through the southern part of the US, my wife and I visited the

Valley of Fire State Park, NV first time in September 2008.

Being interested in historic places, we followed the signs to the Atlatl Rock

petroglyphs not knowing what to expect. We took some pictures of the rock art and enjoyed the beautiful park.

Back home in Germany, when I started to screen the 4000+ pictures I had taken during the four week long trip, I checked the pictures taken at the site and realized, that the shadow of a rock just passed through the concentric circles and the cross of the petroglyps. Being a professional astronomer also interested in the history of astronomy, I had seen similar alignments in books, but never had I expected to see such an alignment myself.

Atlatl Rock, September 12, 2008 at 11:32 am PDT;
ten days before astronomical autumnal equinox 2008

Checking the date the picture was taken it turned out that this alignment was probably set up to mark a specific date. We were there on September 12, 2008 at about 11:30 am PDT, almost the right time so see the shadow pass through the centers of the concentric circles and the center of the cross. Could it be that this alignment was made to indicate the date of the autumnal

equinox that was ten days later?

As it turned out later during my analysis of much more observations I made in the years 2010, 2015, 2017, 2018, and 2023 and the study of publications on the topic, the events indicated by the markings may be some special days around the equinoxes like the days in spring and autumn in the middle between the summer and winter solstices. They may also mark the beginning of the planting season in spring or upcoming ceremonies in fall.

Strangely, despite of intensive search, I could not find any publication mentioning this alignment at Atlatl Rock and on a possible astronomical meaning of the petroglyphs at the site.

Remarks

Many thanks to my wife for her patience all the years during the many mornings she had to spend alone for breakfast at the hotel or at the Atlatl Rock parking lot when I observed sunrise and the movement of the shadow!

A lot of ideas and examples of the use of similar "rock art" by skywatchers of ancient times in the American Southwest are contained in Kenneth J. Zoll's books on his research on petroglyphs and skywatchers in Central Arizona (see [B06] and more recently a summary in [B08]).
Although dealing with people and their rock art south east of the Valley of Fire in Central Arizona, many of the findings in these books were very inspiring and useful in the interpretation of my observations presented here.

The

North Shore Inn at Lake Mead Overton, NV was our base since 2011 (last visit 2018). This nice hotel with its friendly owners and staff is located about 29 km (18 miles; 30 minutes) from Atlatl Rock and is our favorite accommodation there. When temperatures in the valley sometimes reached almost 50°C (120°F), the pool was always a great relief.

In my opinion the

Valley of Fire web site by photographers Isabel and Steffen Synnatschke show the most beautiful photos of this state park. They have issued an

eGuide which is very useful and that I recommend very much.