What's the latest light show in town? Fireflies at the Arboretum.

The Northern Lights get more headlines. Fourth of July fireworks are noisier. But there's another nighttime spectacle that's quietly magical: fireflies.

And you can see them by the dozens at the Minnesota Landscape Arboretum's firefly viewing nights.

Since 2021, the Arb has been open after hours for a handful of midsummer sessions. The popular event draws up to 500 to Chanhassen for the experience. (Remaining viewing nights are July 11-14. Advance tickets required. arb.umn.edu/FireflyNights.)

It starts with a nature presentation about bats, owls and other nocturnal animals as the sun is setting. At dusk, the main event begins, with visitors walking along the firefly-viewing routes, past wildflowers, prairies and wetlands, all of which seem dark and mysterious at night.

Then, here and there, you start to see them: tiny glowing points of yellow lights, randomly flashing on and off in the undergrowth or dotting a grassy hillside.

Fireflies, also known as lightning bugs, are soft-bodied winged beetles that are members of the Lampyridae family of bugs, a name that in Greek means "to shine."

The bioluminescent creatures create light through a chemical reaction involving oxygen combining with two chemicals, luciferin and the enzyme luciferase, which produces a glow through a light-bearing organ on each firefly's underside.

The purpose behind the flashing? It's sex, of course. During their short-lived time as adults, fireflies are lighting up to make luminescent winks at potential mates. But the lights also can be used to attract prey: One genus of fireflies, Photuris, mimics the female flashes of another genus, Photinus, to attract and eat the males of that genus.

The firefly viewing nights were the brainchild of Wendy Composto, the Arb's signature events manager, after she noticed the fireflies in her yard in Eden Prairie in 2020. She realized they would be much more numerous in the expansive (1,200 acres), dark and natural environment of the Landscape Arboretum than in an urban area where there's light pollution.

City dwellers, she thought, also might be surrounded by lawns, which may be too heavily manicured or chemically treated to attract fireflies. And nearby parks may close before it gets dark enough for ideal firefly viewing.

"We don't have the only place, but we do have a good place to see fireflies," Composto said of the Arb. "It's a nice, safe space to come out. I think it's magical to be here after dark."

The frequently sold-out events often include adults who haven't seen fireflies for years or kids who have never seen them.

"A lot of people are just mesmerized by them," she said.

"It's really an awe-inspiring experience," agreed Jason Boudreau-Landis,, a photographer who teaches a firefly photography class at the Arb. "It's a natural light show."

At a recent viewing, firefly watchers listened to performers from the Black Storytellers Alliance presenting African folk tales, fables and myths related to nocturnal animals before heading to the trails. Swallows hunting for their suppers swooped overhead and you could hear creatures stirring in a nearby pond.

The trails were open until 10:30 p.m., and some of the younger kids came dressed in their pajamas, like they would for a drive-in movie.

Ashley Somphet, a Minneapolis resident who wasn't wearing jammies, has been to the viewing nights in previous years, but failed to see any fireflies, possibly because the past few summers have been dry. This year, she was luckier.

Fireflies like moist conditions, Composto explained, and this year's soggy summer has been better for the bugs. "I think we're kind of in a rebuilding year," she said. "When people come out and they see them, they're just so happy."

"I'm hoping to see a lot of fireflies. A big cloud of them, like you see in the movies, would be cool," said Somphet's friend Chris Weatherly of Minneapolis. But "even some of them would be more than you see in the city."

Weatherly said the firefly viewing event was a lot like trying to spot the Northern Lights.

"I think people are here for the same reason: nature's magic," he said.

Firefly fun facts:

• A clap of thunder can cause a field of fireflies to flash simultaneously, which may explain why they're also called lightning bugs.
• The larvae of some firefly species can glow. They're called glow worms.
• There are 2,000 species of fireflies in the world, including 150 species in North America and 19 species in Minnesota. Fireflies can be found on all continents except Antarctica.
• Different species emit different colors. Their lights can be blue, green, orange or yellow.
• Firefly numbers are declining due to climate change, light pollution and habitat destruction. They don't bite or sting or eat plants.
• You can encourage firefly populations by avoiding pesticide use, planting tall grasses and shrubs in damp areas and turning off exterior lights at night.
• Fireflies taste bitter. But some frogs eat them in such large quantities that the amphibians end up glowing.
• If you want to take a good picture of fireflies, you probably won't have much success with your phone, according to Arboretum photographer Jason Boudreau-Landis. You'll want a tripod and a camera capable of taking long-exposure photos.