About this universe
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.
The whys of this universe
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Why are planets round?
Past a certain size, a body's own gravity becomes strong enough to flatten every peak and fill every hollow toward its centre: a sphere is simply the shape a massive object ends up with after falling on itself long enough.
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Why do stars twinkle?
Because their light crosses kilometres of restless air before reaching your eye, and the atmosphere makes that tiny pinpoint dance. Planets, being closer, don't twinkle.
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Why are sunsets red?
Because the light from a sun near the horizon has to pass through a far thicker layer of atmosphere than at noon. The blue is scattered out of the line of sight by the molecules of the air; the red passes through almost untouched. And what reaches you is what's left.
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Why is the sky dark at night?
Because the universe has an age: light from the farthest stars hasn't had time to reach us yet. And the light that does arrive has been stretched so far by cosmic expansion that it has slipped out of the visible range.