Thou shall not pass

A major lunar event at Chimney Rock National Monument will be closed to the public to protect employees, natural resources and the public itself, according to the U.S. Forest Service.

It’s called a “Major Lunar Standstill” (MLS), in which the moon rises between two sandstone spires: Chimney Rock and Companion Rock, as viewed from the Great House Pueblo atop the monument. Many archeologists believe the Ancestral Puebloans in part chose Chimney Rock because of this phenomenon (the Great House was possibly built in 1093, during an MLS event). However, this is still up for debate.

An MLS happens every 18.6 years, but here’s a caveat – at the end of each cycle, the moon pauses for about three years. The last MLS happened in December 2004 and lasted for three years. The moon is visible between the spires for a few days throughout the year over this three-year period. It’s obviously much more complicated than that, and you can read about more about the intricacies of the MLS at chimneyrockco.org.

Previously, the public could view the MLS from a fire lookout tower. But the tower was removed in 2010, and there is no place  that can host visitors, the Forest Service said. With all the risks to the public, the agency decided to close off the monument.

“Hazards associated with hiking the strenuous upper mesa trail in the dark, significant 1,000-foot cliffs on both sides of the trail, and the lack of adequate safety lighting and cliff barriers have been determined to be beyond the agency’s ability to mitigate,” the Forest Service said in a statement.

Roads closure include FS Road 617 and 617.A, as well as the Great House Trail from 4:30 p.m. - 6 a.m. In 2023, the closure dates include: July 15-16, Aug. 11-12, Oct. 3-5, Oct. 31-Nov. 1-2, Nov. 27-29 and Dec. 25-26.

The Forest Service said it is exploring ways to share the event in 2024-25, either through live streaming, still photography and/or video recording.

And we know what you’re thinking, and stop. Hiking in at night will do you no good, as the moon rise between the spires is only visible from a small area along a cliff edge. Plus, hiking in the dark puts you and others at risk. And, if that wasn’t enough, Forest Service staff will be hanging out to deter would-be scofflaws.