Mule Ears Under Airglow

Big Bend National Park, Texas

This frame came from a timelapse I shot at the Mule Ears Viewpoint.

I was set up for motion, not for a single hero composition. Wide. Horizontal. Enough sky to let the Milky Way travel cleanly across the frame as the hours passed.

The formation in the distance is the Mule Ears, one of the most recognizable silhouettes in Big Bend National Park. Almost everyone who spends time in the park eventually ends up here. It’s accessible, distinct, and unmistakable against the horizon.

If I were shooting this as a standalone photograph, I would likely compress the scene more. A longer focal length tightens the relationship between the twin volcanic spires and the sky. Or I’d hike closer and let them carry more visual weight. But often for Milky Way timelapse work, the sky is the subject. I love placing cactus and subjects in the extreme foreground as well, but I needed a clean flat scene for this project.  

The green glow beneath the Milky Way is natural airglow, faint to the eye but persistent in long exposures. It’s one of the subtle gifts of dark skies in West Texas. You don’t normally notice it when you’re standing there. The camera does.

There’s nothing complicated about this image. It’s a familiar location, a clear night, and a reminder of how consistent Big Bend can be when the weather cooperates.

Context and Landscape

The Mule Ears are twin volcanic dikes rising from the western side of Big Bend National Park. Formed millions of years ago during periods of volcanic activity that shaped much of the Chisos region, these resistant rock spires remain after softer surrounding material eroded away. Their name comes from their distinct silhouette, resembling the ears of a mule when viewed from certain angles along Ross Maxwell Scenic Drive.

This area sits within the Chihuahuan Desert, one of the most biologically diverse deserts in North America. Creosote bush, ocotillo, sotol, and lechuguilla dominate the foreground, adapted to heat, minimal rainfall, and dramatic temperature swings between day and night.

Big Bend National Park is recognized as an International Dark Sky Park, and its remote location along the Texas-Mexico border keeps light pollution extremely low. Under clear conditions, the Milky Way core becomes visible to the naked eye during the right season, stretching across the sky in dense bands of star clouds and dark dust lanes.

Airglow, visible here as a soft green band near the horizon, is a natural atmospheric phenomenon caused by chemical reactions in the upper atmosphere. It is present most nights, though its intensity varies. In long exposures and timelapse sequences, it often reveals itself as a subtle wash of color beneath the stars.