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Main content
Cosmology and astronomy

Scale of the universe

Cosmology and astronomy

Scale of the universe

Lessons

Scale of earth, sun, galaxy and universe

Learn
Scale of the large
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Scale of the small
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Scale of earth and sun
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Scale of solar system
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Scale of distance to closest stars
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Scale of the galaxy
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Intergalactic scale
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Hubble image of galaxies
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Time scale of the cosmos

Learn
Cosmological time scale 1
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Cosmological time scale 2
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Light and fundamental forces

Learn
Introduction to light
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Four fundamental forces
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Big bang and expansion of the universe

Learn
Big bang introduction
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Radius of observable universe
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Radius of observable universe (correction)
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Red shift
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Cosmic background radiation
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Cosmic background radiation 2
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Hubble's law
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A universe smaller than the observable
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How can the universe be infinite if it started expanding 13.8 billion years ago?
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About this unit

Things in our universe can be unimaginably large and small. In this topic, we'll try to imagine the unimaginable!