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Oiseaux · Ciel
Quaé Plumaire, mascotte de Quarelia
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Plumaire

Birds · Sky

7 whys told, 3 on video

  • birds
  • flight
  • migration
  • weather
  • clouds
Start with the most surprising

The whys of this universe

An adult pigeon stands on a building cornice; below it, in the shadowed recess, an almost invisible squab sits in a nest of twigs.
  • Oddity
  • Video 38 s
  • 4 min

Why do we never see baby pigeons?

You pass young pigeons every week without knowing it. The reason comes down to a cliff-side nest and a few weeks of patience.
Two eclipsed suns side by side in a very pale sky, framed by blue clouds rising on either side: the left one keeps a wide crescent of light, the right one only a thin sliver. Below each, a bird in deep navy silhouette — the left one with its beak open, singing, the right one with its beak shut.
  • Video 33 s
  • 4 min

Why do birds fall silent during an eclipse?

The silence isn't fear. Birdsong answers to light, and four minutes of artificial night are enough to derail the clock that triggers it.
At dawn the air is still, sound carries far, the light is too thin for hunting: the best moment to advertise that you're alive and in good shape.
  • 3 min

Why do birds sing at dawn?
Droplets so small they fall almost infinitely slowly: a faint upward breath is enough to hold them.
  • 3 min

Why do clouds stay up?

The water in a summer cumulus weighs as much as seven or eight blue whales. Its droplets are so small they would take 28 hours to fall a single kilometre.
The first pressurised airliners had nearly square windows. Two came apart in mid-flight in 1954: a corner concentrates stress where a curve disperses it.
  • Oddity
  • Video 1 min
  • 4 min

Why are aircraft windows round?

A whole Comet fuselage was sunk in a water tank and pressurised 3,000 times before the metal split. The crack started at the corner of a window.
Neither a whim nor an exercise: the posture saves heat, and a passive joint mechanism lets the bird stand effortlessly, even asleep.
  • Oddity
  • 4 min

Why do flamingos stand on one leg?
Blue light zigzags between air molecules and reaches us from everywhere at once. A sky that breathes: not a Rayleigh diagram, not a rural landscape.
  • 3 min

Why is the sky blue?

Violet scatters even more than blue, yet the sky is blue: the Sun emits less violet, and our eyes are less sensitive to it. Rayleigh explained it in 1871.

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Plumaire on video

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Plumaire is everything that holds in the air, in feathers or in droplets. Here you learn why aircraft windows are round, why flamingos stand on one leg, and why the sky is blue. Come evening, that same sky changes its hue, and turns red.

Espace · Cosmos

Space · Cosmos

Cosmira

The universe next door

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Cosmira is the night sky that never ends, where every question is measured in light-years. We look at Jupiter, black holes, and comets with the kind of humility that keeps you curious.

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