The camera shutter closed, a digital photo appeared on the LCD on the back of my camera, and suddenly a throng of people surrounded me. With wide eyes they glared at the photo, back to the thundering Cumberland Falls, and back to my camera again. Finally, someone shouted, “I see it! I can see it in your photo!”
The “it” she was referring to was the Cumberland Falls Moonbow, a spectacular lunar rainbow that can be seen in the mist at Cumberland Falls State Resort Park in Kentucky. But you have to know when to see it, how to get there, and what to expect. Keep reading to find answers to all that and more.
What is a Moonbow?
The first time I visited Cumberland Falls State Resort Park was on an overcast day in 2012. The waterfall was pretty amazing to see even if I couldn’t capture any decent photos that day. But just as I was leaving the park a ranger asked me a question that would change everything, “Are you coming back tomorrow for the moonbow?”
It was the first time I’d ever heard of a moonbow so I asked about it. A “moonbow” is when light from a full moon on a clear night reflects in the mist of a waterfall and creates rainbow colors in the moisture. But this doesn’t just happen during any full moon or at any waterfall; there are certain conditions that must be met to create a moonbow.
Cumberland Falls just happens to be one of the best places in the Western Hemisphere to meet all these conditions.
It takes quite a bit of light to create a rainbow. In fact it normally takes direct sunlight beaming through the sky to create the optical illusion in the sky.
But even during a full moon only about 13% of the sun’s light is reflected down to Earth. That’s why even under the best of conditions a moonbow is still a tricky and difficult thing to see.
Because a moonbow requires every lux of light available it really needs to be a cloudless night. Even a thin haze can prevent a moonbow from appearing if all the other conditions are met.
Lots of Moisture
Even on a cloudless night during a full moon you won’t see a moonbow above every waterfall. It takes a lot of moisture in the air to refract the light and create the optical illusion.
Cumberland Falls is known as the “Niagara of the South” because it is a rather large waterfall. It only has a 68’ drop but at 125’ wide Cumberland Falls has more water volume than any other waterfall on the East Coast south of Niagara Falls.
The Perfect Combination
In order to see the moonbow you need to visit Cumberland Falls when lots of water is flowing, within one or two days of a full moon, and on a completely cloudless night. Getting those three conditions to align is tricky, but it actually happens pretty regularly at Cumberland Falls State Resort Park.
Seeing the Cumberland Falls Moonbow
About a year after learning about the Cumberland Falls Moonbow I returned to the state park to see it. I had spent my day nearby in the Big South Fork National River & Recreation Area. I was exhausted from all the hiking but nothing was going to stop me from seeing the moonbow.
The large parking lot was brightly lit (but don’t worry it doesn’t ruin the moonbow) and nearly full. There were several park rangers helping people out and guiding them toward the moonbow. Just to let you know how much the park loves this natural event: the trail is called the Moonbow Trail.
Although there are several places to admire Cumberland Falls there is only one place to see the moonbow: the Upper Overlook. This overlook is less than a five-minute walk along a paved path from the visitor center. It’s located on exposed rocks beside the top of the falls so be careful walking out there at night.
That night I set up my tripod, dialed in the camera settings, and fired off the first photo. One thing you have to keep in mind is that it’s a little difficult to see the moonbow with your naked eyes. Long exposure photos actually work much better.
People were craning their necks, shining flashlights at it, hoping to catch a glimpse. The shutter clicked on my camera. A photo appeared on the LCD screen. Suddenly I was surrounded by a throng of people all eagerly looking at the brightly-lit long exposure photo. Finally, a nice old lady shouted, “I see it! I can see it in your photo!”
Just like that, I was a celebrity. Lasted about ten minutes.
Moonbow Dates 2019
The absolute best day to see the Cumberland Falls Moonbow is the day of a full moon. However one or two days before and after are also good times and under just the right conditions can create a beautiful moonbow.
Here are the Cumberland Falls Moonbow dates for 2019.
Parking for the Moonbow
The visitor center parking lot at Cumberland Falls State Resort Park is pretty big, but you have to keep in mind sometimes there are thousands of people who try to witness the moonbow. Parking will go quickly.
My suggestion is to arrive as early as possible for the moonbow to guarantee a parking spot, but if all else fails give the state park a call. They usually have some plans set up for massive crowds.
Admission for the Moonbow
Maybe the second best part about the Cumberland Falls Moonbow is that it’s free! In fact access to this state resort park is always free.
Tips for a Fantastic Experience
Here are a few tips to help you make the most out of your trip to witness the Cumberland Falls Moonbow.
- Arrive early. You won’t be able to see the best effect of the moonbow until about an hour after sunset, but I would still recommend arriving early to snag a parking spot.
- You won’t be able to see the moonbow until about an hour after sunset, so time your visit according to the Moonbow schedule above.
- Because of time change (yuck) and the Earth’s tilt the moonbow is much earlier during the winter months, and sometimes well after midnight during the summer months.
- Bring a flashlight or headlamp. For obvious reasons there are no street lamps or lighting around the Upper Overlook. But be careful not to shine the line in anyone’s face or toward any cameras.
- For the best experience book a couple of nights at DuPont Lodge in the park. It’s just a 0.5-mile hike down from the lodge to the visitor center parking lot along the Cumberland Falls Trail.
Photography Tips for Capturing the Moonbow
Before I get into camera settings and equipment I have to stress one thing above all others: put your cellphone away. Seriously. You will not be able to capture a decent photo of the moonbow with a cellphone. But if you do just have to give it a try let me stress a second thing: turn the flash off. There is nothing worse than your eyes dilating, adjusting to the dim moonlight, trying to see the moonbow, only to have a flash pop off from a cellphone. Don’t be one of those people.
Here are a few tips for camera equipment and settings to capture a photo of the Cumberland Falls Moonbow:
- Bring a tripod.
- Bring a remote shutter release. You may need to do a very long exposure so the best shutter release would be a digital intervalometer.
- Set your ISO to 400. If you have a newer camera model with better low-noise at higher ISO settings you can try 800 or 1600, but I wouldn’t recommend beyond that with even the best of cameras.
- Start with an exposure of 2 minutes at 400 ISO, 1 minute at 800 ISO, and 30 seconds at 1600 ISO. Most camera models only allow for a 30-second maximum exposure with the built-in settings. This is why you need a digital intervalometer remote shutter release; these allow you to use the “bulb” exposure setting and shoot as long as you like.
Have You Seen the Cumberland Falls Moonbow?
If you’ve seen this absolutely extraordinary natural event leave me a comment below and tell me all about it! Seeing the Cumberland Falls Moonbow was one of the most rewarding experiences all year and that photo has been one of my favorites ever since.