Sort Sol

Sort Sol — "black sun" — is one of northern Europe's great natural spectacles: tens of thousands of starlings gathering over the Danish Wadden Sea each spring and autumn, dancing across the evening sky in rolling black bands.

This app simulates it. There is no video in here — the flock is computed while you watch, thirty times a second, bird by bird.

IN YOUR OWN SKY Point the phone up, tap, and the flock is standing in your own view. The sun's position is worked out from the time and the place you're in, so the light on the wings matches the evening you're actually standing in. You can also watch it without the camera, against the app's own dusk sky.

NO BIRD IS STEERING Each bird watches its seven nearest neighbours and matches them. That's all. The bands, the waves, the sharp edge and the sudden turns emerge on their own once tens of thousands do it at once — exactly as they do over the marsh. It never looks the same twice.

THE EAGLE Send the white-tailed eagle hunting and panic spreads through the flock as a wave. A hole opens around it, the flock compresses and stretches — and afterwards slowly finds its shape again.

DUSK Send the flock down into the reed bed for the night and watch it draw together into a spiralling funnel. Call it back up whenever you like.

RECORD AND SHARE Capture fifteen seconds of your own black sun, save it to Photos, and share it.

SOUND The chatter of the roost, if you want it. It respects the silent switch and mixes with whatever you're already playing.

TURN THE DIALS Flock size, flight speed, cohesion, restlessness, wind, the eagle's reach, the shape of the reed bed. Adjust all of it — or none of it. One tap puts everything back to our own Sort Sol.

No account, no sign-in, no data leaving the phone. The camera and your location are used only to show the flock and to work out the sunlight.

AR mode requires a camera and an ARKit-capable device.

Photos by James Wainscoat on Unsplash Image by AvnesZ on Pixabay

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