Under certain conditions, light can also produce colorful patterns around cloud edges.
Cloud iridescence occurs when sunlight is diffracted by very small, similarly sized water droplets or ice crystals.
The result can be pastel colors, often appearing close to the Sun.
These colors may be subtle, and they are not necessarily visible in every photograph.
Halos and coronas
Halos form when sunlight or moonlight interacts with ice crystals in high-level clouds.
They often appear as rings around the light source.
Coronas are different optical effects involving diffraction by small water droplets.
Although neither phenomenon can be confidently identified in the supplied image, both demonstrate how ordinary atmospheric particles can produce remarkable visual effects.
9. Could the Image Show a Hole-Punch Cloud?
Another cloud phenomenon that frequently attracts attention is the cavum, also known as a hole-punch cloud or fallstreak hole.
These formations can look as though a large circular or oval section has been removed from a cloud layer.
Sometimes wispy trails of ice crystals appear inside the opening.
The effect can be so unusual that people mistake it for a hole created by a spacecraft or an unexplained object.
NASA explains that these formations can develop when aircraft pass through layers of mid-level clouds containing supercooled liquid water droplets.
The aircraft's passage can help trigger the droplets to freeze. Ice crystals then grow and fall, leaving a visible gap in the cloud layer.
The resulting opening may be circular or elongated, depending on the circumstances.
Why do people mistake them for something extraordinary?
Most people are familiar with ordinary clouds but rarely see the processes that create unusual cloud formations.
A large circular opening in a cloud layer is therefore surprising.
If the opening is illuminated by sunlight or contains falling ice crystals, it can look even more dramatic.
Photographs of cavum have sometimes prompted speculation about unidentified flying objects.
However, scientific research has established an atmospheric explanation for this particular phenomenon.
NASA Science+2
The photograph supplied here does not clearly show the circular opening associated with a typical cavum. It would therefore be inappropriate to label it a hole-punch cloud.
Still, the phenomenon is a useful reminder that unusual cloud structures can have explanations that are not immediately obvious to an observer.
10. What Would Meteorologists Need to Identify the Formation?
A single photograph can offer clues, but identifying an atmospheric phenomenon often requires several types of information.
Meteorologists do not rely only on whether a cloud looks unusual.
They consider the conditions in which it formed.
The time of the photograph
The exact time helps establish the position of the Sun or Moon.
If the photograph was taken shortly after sunset, lingering sunlight may have illuminated high clouds.
If it was taken late at night, artificial lighting or moonlight may be more relevant.
The time also allows investigators to compare the photograph with weather observations.
The location
The reported distance of 21 kilometers from the photographer's home is interesting, but the precise location would be even more useful.
Meteorologists could examine nearby weather stations, cloud observations, terrain, and atmospheric conditions.
If the area is near mountains, for example, certain cloud formations may be more likely.
If it is near a large urban area, artificial lighting may be a reasonable possibility.
Wind direction and speed
Clouds are constantly moving, even when they appear stationary from the ground.
Wind speed and direction at different atmospheric levels can help explain the shape and movement of a formation.
A video showing the cloud over several minutes would provide valuable information.
Temperature and humidity
The temperature and moisture content of the atmosphere influence cloud formation.
Some unusual formations occur when moist air rises, cools, and condenses.
Others are associated with supercooled droplets or ice crystals.
Weather records can help determine whether the conditions were suitable for a particular cloud type.
Original photographs and videos
The original files are especially important.
They may contain metadata showing the time, date, camera settings, and other useful information.
A sequence of photographs can also reveal whether the bright shape changed position or appearance.
A screenshot of a social media post cannot provide all of these details.
For that reason, a reliable identification should not be based on the visible outline alone.
11. Why Four Photographs Can Make One Formation Look Even More Mysterious
The supplied picture contains four views of what appears to be the same bright formation.
This presentation invites viewers to compare the shape from one frame to another.
At first, the repetition may make the formation seem more convincing. If the same outline appears several times, people may assume that it represents a solid object or a clearly defined figure.
But there are several other possibilities.
The four images might be separate photographs taken seconds apart. They might be enlarged crops of one original image. They could also be screenshots or edits assembled into a collage.
Each possibility would affect how the image should be interpreted.
If they were taken seconds apart
Clouds can change their outlines surprisingly quickly.
Wind moves droplets and ice crystals through the atmosphere, causing edges to expand, disappear, and reform.
A bright area may become larger or smaller as the cloud shifts relative to the light source.
If the four photographs were taken in sequence, they might show the same natural formation changing over time.
If they are enlarged crops
Cropping removes much of the surrounding information.
A wide cloud formation may look like a recognizable figure when only a small section is shown.
The original photograph might reveal that the apparent figure is simply part of a much larger cloud layer.
If they are edited versions
Adjustments to brightness, contrast, sharpness, and color can make certain details stand out.
This does not automatically mean that an image is fake. Ordinary editing can change the visual impression without changing the underlying subject.