Sun Daggars!

This is super cool.

I’ve always been interested in how people track time, during the day and across the seasons. I’ve posted about the sundial of Augustus in Rome and the obelisk of St. Peter’s, the sunclocks of St. Sulpice in Paris and in Santa Maria degli Angeli in Rome. I think I may have posted about the astrolabe I have tucked away somewhere. Etc.

From APOD:

Explanation: Ancient sun daggers will not hurt you, but they may tell you the time. A sun dagger is a dagger-shaped gap in a shadow created by sunlight streaming through a crevice in a nearby rock. Starting over a thousand year ago, native people of the American southwest carved spiral petroglyphs into rocks that became illuminated by sun daggers in different ways as the Sun shifts in the sky. A type of sundial, where the end of the sundagger points in the spiral at high noon (for example) indicates a time of year, possibly illuminating a solstice or equinox. Sun daggers are thought to have been used by Sun Priests during lone vigils with prayers and offerings. Of the few known, the featured video discusses the historic Picture Rocks Sun Dagger near Tucson, Arizona, USA, likely created by a Hohokam Sun Priest around 1000 AD.

For the links in that piece, go over to APOD.

About Fr. John Zuhlsdorf

Fr. Z is the guy who runs this blog. o{]:¬)
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  1. grateful says:

    That is “just too cool”. Thanks Father.

  2. Semper Gumby says:

    Here’s a bit more on archaeoastronomy and the Hohokam. The Hohokam of the desert Southwest probably had the most extensive system of irrigation in ancient North America.

    The “morning star” in Isaiah 14:12 refers to Satan, in 2 Peter 1:19 and Rev 22:16 it refers to Jesus. This is similar to Satan as a “roaring lion” and Jesus as the Lion of Judah. Victory is assured.

  3. Greg the Geologist says:

    There’s another little-known chapter to this story. Some of the Spanish Mission churches in the Southwest were oriented to cause illuminations of the tabernacle or patron saint statues or other images on feast days or the winter solstice. Professor Ruben Mendoza has done groundbreaking and original research to document this: Now that’s inculturation!

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