Seattle Astronomical Society The Webfooted Astronomer << Previous Page Next Page >>

The Webfooted Astronomer - September 1999


Minutes: Ancient Petroglyphs Measure Astronomical Time

by Leslie Irizarry

The August SAS meeting was held on August 18, 1999, at 7:30 p.m. in the UW's Physics-Astronomy Building.

President Karl Schroeder began the August Seattle Astronomical Society (SAS) meeting by suggesting that too much "hot air" on top of Table Mountain this year may have caused the weather to turn lousy. However, after many people left on Saturday night, the skies cleared for good observing until 3 a.m.

Worldwide Software Publishing is offering special discounts on their SkyMap Pro 5 software for SAS club members. See Karl for brochures on this software. Light Pollution Warning: Around August 20, the City of Seattle will install upward directed lighting on the George Washington Bridge (Highway 99), which will generate additional light pollution. Our organization might look in to writing a letter to the City of Seattle's Department of Construction and Land Use explaining suggesting an alternate form of lighting should be considered to reduce waste and unwanted light pollution.

Awards Banquet: The club is considering the Space Needle as a potential banquet site for the January 2000 awards banquet. It would cost about $30 per person if we could get at least 70 people to sign up. Ken Applegate recommended that other sites also be considered in order reduce the price of the banquet tickets.

Al McFarlane announced he has some "Big Bang" theory books that he is getting rid of. Interested SAS members should contact Al for the books.

Pat Lewis announced that Viva La Lune will be held this Friday after the meeting.

Keith Allred Astrophoto SIG will be held the first Sunday in September at 2 p.m. Contact Keith for more information.

Ancient Petroglyphs
John Rudolph of the Battle Point Astronomical Observatory on Bainbridge Island, talked about petroglyphs, which may be records of astronomical observations by American Indians

John has explored sites in the western United States that contained petroglyphs of what may have been records of astronomical observations conducted by Native Americans hundreds or even thousands of years ago. The first site John discussed was Willow Creek near Susanville California. The second was on Bainbridge Island.

Willow Creek is above the Great Basin Area. There is an escarpment of basalt 200 feet above the stream bed where two “chambers” exist. On the northern end, a little crack forms a cave. Back 27 feet into the cave exists a petroglyph 18 inches across. It consists of a serpentine line with a circle with a dot in the middle. This could be the sun or moon. The serpentine can be used as a counter, with each peak representing a month. On a grid-like petroglyph, the shadow of the rising sun fits on top of this at the winter solstice. Another petroglyph appears as a circle with a line and two dots within it. That symbol is also found in Ireland and is also one of the letters of an early Norse alphabet. John speculates that people were moving around the globe long before the documented discovery of America.

The moving sun cuts a triangle on back wall of cave. On the day of the summer solstice. a shaft of light illuminates the rock. On another glyph he calls the "Sunset Mask," the sunlight light moves around the edge of the sunset mask on the afternoon of summer solstice.

Some of the petroglyphs may have used gauges to predict lunar and solar eclipses. Another quite elaborate glyph could possibly be a representation of a portion of the northern Milky Way. Notches in the stone roughly match some star patterns. Could this have been an early Indian star map?

Another petroglyph exists on Bainbridge Island. The circular figures on this rock may be depictions of the rising moon. The rock is in a tidal area and is sometimes covered by sea water. From the same area, one can see a “notch” in the Cascade Mtn. Range which is aligned with sunrise / moonrise points on the horizon at various times throughout the year.

Top of Page