Zigzagging circles of light on the clouds? Probably an advertising searchlight

5 min read

Bright, round spots zigzag, circle and cross each other on the clouds, sometimes spinning in a circle. They come from above, and nothing can be heard. Sights like this are regularly reported as UFOs, yet often they are the advertising searchlights of a disco, event or light show projected onto the cloud base, even from kilometers away.

What do people see in these cases?

The reports are similar: on an overcast, cloudy night, strong white circles of light appear on the clouds. They move fast, zigzag, spin in a circle, sometimes converge and then separate, as if flying in formation. The lights seem to shine from behind the clouds or through them, and no sound accompanies them.

What is an advertising searchlight?

An advertising searchlight is a high-power, movable spotlight used by nightclubs, events and stores to draw attention to themselves from far away. The larger types use xenon lamps. According to a manufacturer's manual, a 2000-watt lamp has an intensity of about 208 million candelas per beam, and the beams of the four-head versions move in a cloverleaf pattern, completing one circle about every 6 seconds. According to a German nature-conservation article, disco searchlights are typically 1000–2500 watts.

Smaller, music-controlled stage lights can also produce a similar effect. In the 2022 Wisconsin case, the phenomenon was caused by the 380-watt moving-head party lights of a family Christmas light show.

Why does it look like a UFO?

The secret is the cloud base. According to BBC Sky at Night magazine, from a distance the beam is so faint that it isn't even visible, only the bright spots projected onto the clouds. This makes it seem as if the light were shining through the clouds from above, rather than hitting the cloud from below.

According to an analysis on the Metabunk forum, the beam is hard to see even from a few kilometers away, while the spot appearing on the cloud is much brighter and can be noticed from more than 15 km away. Because the searchlights are moved by a person or a computer, often to music, the motion of the spots looks irregular and zigzagging from a distance.

Real cases

Wisconsin, December 1, 2022: an American UFO researcher posted videos of bright lights moving in formation below the clouds, from the area around Fredonia, Wisconsin. By determining the location and direction of the footage, analysts on the Metabunk forum traced them to a family Christmas light show about 17 km away. The family confirmed that they have six moving searchlights (one was not working that day, so five), and the pattern of the lights matched their show's programming. The cloud base that day was at about 2000 meters.
Norfolk, Virginia, November 2022: for days, residents saw fast-moving orbs of light zigzagging in sync on the clouds. In response to an inquiry from WAVY-TV 10, a spokesperson for the Nauticus maritime museum stated that the lights were the searchlights of a winter light festival held on the battleship USS Wisconsin, and that they were reflecting off the clouds.

It's not only observers they bother

Advertising searchlights are one of the most visible forms of light pollution. According to the German nature-conservation article, they can also disturb migrating birds: cranes may circle in the beam for hours, and a searchlight about 25 km away even startled a flock of cranes and geese at a resting site. At a Dortmund disco's searchlight, about a thousand moths and other larger insects died within one hour. In Germany, several court rulings have favored a ban, and in most places their use requires a permit.

How can you recognize it?

Only visible in cloudy weather: the circles of light appear on the cloud base. On a clear night there is nothing for them to be projected onto; then at most the beam itself is visible near the light source.
The spots move around a single point: they circle, zigzag, converge and separate, but always stay above roughly the same area.
Repeating pattern: the motion repeats within minutes, because it is controlled by a machine or by music.
No sound: the light source is far away, and no sound can be heard.
Round or oval spot with blurry edges: it has no sharp outline, and it can distort as the clouds move.
If you get closer, the beam becomes visible too: near the light source, the beam is clearly visible from the ground to the clouds.

If the lights appear below the cloud base, in front of the clouds, or move in a clear sky without clouds, the cause may be something else. In that case, it is worth considering sky lanterns, drones or airplanes too.

The sober take

What is it? Advertising searchlights are high-power, movable spotlights used by nightclubs, events and light shows. On a cloudy night, their beams appear as bright spots on the cloud base, and because the beam is barely visible from a distance, the spots look as if they were independently moving, glowing objects.

Key signs for recognizing it:

Only visible in cloudy weather, on the cloud base.
Round or oval, blurry spots of light that circle, zigzag, converge and separate.
They always stay above roughly the same area, and the motion repeats.
No sound, often in the direction of a town, nightclub or event.

How does it differ from a genuinely unidentified light? The searchlight's spot is always on the cloud, and it distorts along with the cloud. If the light appears below the clouds, in front of them or in a clear sky, if it travels a long way in one direction, or if it does not return to the same place from one day to the next, the cause may be something else.