Category Topics


The documentation category contains information written for and by everyone, from the curious ones that don’t know anything about these phenomena, to the more interested folks that want to learn more about them.

Ice Halos

Bright white or rainbow-colored, having a wide variety of shapes and positions in the sky, discover the wonders of ice halos, created by sunlight reflecting, refracting and scattering in ice crystals suspended in the atmosphere.

Sun Rays And Shadows

Sun and other light sources playing with their light and cast shadows, sometimes in unusual ways.
See the Earth’s own shadow cast in its atmosphere, plane contrails having their shadow twin, rare “green flashes” and others.

Water Droplets

Light reflecting and scattering through water droplets in the rain, clouds, fog, dew…
Discover fog bows, Brocken spectre, cloud iridescences, etc. Even rainbows have unusual displays and hidden secrets.

Unusual Clouds

You’ll find here rare and strange cloud types or formations.
Spiral, roll, wall or bubble-shaped clouds, nacreous or other high-altitude ice clouds that offer unusual spectacles.

Other Atmospheric Phenomena

This category contains what doesn’t fit in other categories: polar auroras, mirages, lightning storm-related phenomena, etc…

Sighting Identification Help

You’ve spotted something strange in the sky? You’re wondering what it is?
You’ve captured complex displays that need further identifications or research?
Provide pictures or videos, and the community will help you.

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