Ancient sky watchers’ use of petroglyphs is the topic of the upcoming Smoky Hills Audubon Society program.

The program is scheduled for 7:30 p.m. Thursday in 229 Peters Science Hall at Kansas Wesleyan University. Peters Science Hall is on Cloud Street on the east side of the KWU campus. The meeting is open to the public at no charge. Those attending may arrive up to a half hour early in order to meet the speaker prior to the program.

Crystal Trickle is a part of a field team that is searching Kansas for ancient astrological alignments that are only revealed at sunrise on a single day of the year.

On Thursday, Trickle will explain how by leaving petroglyphs on ancient rock walls to record the alignments, ancient Native Americans put order in the celestial events. With the use of the sun and simple stone, they not only developed calendar sites to keep time and track the movements of the heavens but within their design, were able to include hidden features capturing the light of the sun.