Rare moonbow shines below total lunar eclipse in stunning photo: 'This is definitely the first time I've tried something like this, but will not be the last'

Earlier this month, a total lunar eclipse was visible across Earth and the U.S. was in prime position to see the very best of this spectacular event overnight on March 13.

Over several hours, stargazers watched in awe as the moon's shadow slowly crept across the lunar surface, turning our nearest celestial neighbor blood red.

Billy Buchanan (Narcoleptic Nightscapes) managed to capture not only a stunning total lunar eclipse sequence but also a rare moonbow, from Cumberland Falls State Park in Corbin, Kentucky. "This is definitely the first time I've tried something like this, but will not be the last," Buchanan told Space.com in an email.

What is a moonbow?

A moonbow, or lunar rainbow, is a rare phenomenon that occurs when moonlight is refracted, reflected, and dispersed by water droplets in the air, just like a daytime rainbow.

Because moonlight is much fainter than sunlight, moonbows are usually white or very faint in color and are best seen on dark, clear nights when the moon is bright — typically near a full moon. Unlike daytime rainbows, moonbows require long exposures in photography to reveal their full spectrum of colors to the human eye.

It wasn't all plain sailing

This final image required not only meticulous planning and post-production but also perseverance, a bit of luck with the weather, and some heavy lifting!

"I need to acknowledge and thank Mike Shaw and Glenn Randall for helping me to refine and think much more critically about what it might take to pull this off and what potential pitfalls could derail the idea," Buchanan told Space.com.

Despite the weather forecast for clear skies overnight from March 13 to March 14, Buchanan experienced a weather warning of strong winds and hail when he was about 20 miles from his chosen photography site.

"It started raining when I was lugging all the gear I had to the spot where I wanted to set up; altogether I was carrying/rolling about 135lbs of gear/equipment/creature comforts, of which 40lbs were weights for the tripod that would have the panorama head to make sure it didn't move at all," Buchanan said.

Cloud cover to the north persisted for a while which delayed when Buchanan and prevented him from capturing his initial idea of a blue-hour foreground shot.

Capturing the ultimate moonshot

To capture this stunning panoramic image of the total lunar eclipse and moonbow, Buchanan used a Nikon Z9 camera with a 20mm wide-angle lens and a special panoramic tripod head to stitch multiple images together. The final image is a combination of different exposures taken separately for the sky, foreground, and the moon itself.

For the sky, Buchanan used a shorter exposure (10 seconds) to reveal the stars while keeping the landscape crisp. The foreground required much longer exposures — up to two minutes — to bring out the details in low light. The moon, on the other hand, needed different settings throughout the eclipse, with lower sensitivity (ISO 200) before totality and a higher setting (ISO 800) during totality to balance brightness.

Because the moon moved across the sky throughout the night, Buchanan told us he had to carefully blend multiple images to create its arc in the final panorama. Some moon images had to be duplicated and adjusted slightly to maintain the natural progression.

Processing involved stitching the images together using specialized software known as PTGui, adjusting brightness and colors to match different sections of the sky, and reducing noise to enhance clarity.

Buchanan was not sure that he would be able to capture this scene the way he had initially envisioned.

"To capture the moonbow in the scene I knew I would need to use some type of panoramic approach, but knew the exposures of the moon would be much more difficult to incorporate into a panorama if I wanted to expose the moon and not the scene," Buchanan said.

"Initially, I considered capturing a panorama at each interval and layering all of the stitched panoramas to mask in the moons," Buchanan continued. "Even with all of the foot traffic, flashlights, and bright-screened mobile devices I quickly figured out that strategy would not work. So, I shifted my strategy to capturing the foreground, sky, and moons separately and stitching it all together".

In the end, this method worked beautifully, allowing Buchanan to create an image better than the one he had envisioned. "When I saw the first version where I masked the moons into the sky panels and stitched the panorama together, I knew instantly that it turned out better than I had planned."

"The respective sizes of the two arcs also create a great symbolic representation of the difference in scale between what we experience and deal with as humans on Earth and the vastness and grandeur of the scale of space and our closest neighbor," Buchanan stated.

Editor's Note: If you snap an incredible night sky photo and would like to share it with Space.com's readers, send your photo(s), comments, and your name and location to spacephotos@space.com.