Gordon Houston, Solar System Ambassador and lifelong observer of the sky, gave us a great talk about Rock Art Solar Markers. His research has primarily been at the Texas site of Paint Rock which is about 30 miles east of San Angelo. Rock Art refers mostly to pictures or symbols left on rock surfaces by members of traditional cultures. Some rock art was created at least 10's of thousands of years ago. To learn more about this subject, check out the following websites.
http://www.arara.org/ or
