Four decades ago, two American astronauts walked the moon for the first time. That same year, the International UFO Symposium held its first meeting. Next month, a dozen speakers—such as physicist Stanton Friedman and Roswell, New Mexico researcher and author Kevin Randle—will appear in Denver for the symposium’s 40th anniversary gathering, writes the Colorado Springs Gazette.

Presenters are expected to discuss new evidence of sightings across North America, scrutinize photos, talk about the search for extraterrestrial life, and challenge government secrecy about UFOs. A group of symposium-goers will even hold a conference with news reporters at the Marriott Tech Center on August 7 at 11 a.m. to highlight UFO sightings over Colorado.

Earlier this month, the Aspen Times was among newspapers to quote Silverthorne resident Rod Pscholka and two of his friends who spotted a strange object in the sky.

“We couldn’t tell what we were seeing,” Pscholka said. “It was maybe 15-feet long. It was pretty weird, whatever it was. Maybe it’s the Air Force.”