Science Ages 14-18 ● Media ready

Cosmology and astronomy

It's a great, big universe out there. In this section of Khan Academy, you'll learn about the brain-bending vastness of time and space. We go from plate tectonics here on Earth to entire galaxies and beyond.

4 units 17 lessons 100 videos 32 on CDN

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Unit 2 Scale of the universe

1 Scale of earth, sun, galaxy and universe Free 7 video(s) ● 2 Time scale of the cosmos Free 2 video(s) ● 3 Light and fundamental forces Free 2 video(s) ● 4 Special relativity 🔒 Pro 21 video(s) ● 5 Big bang and expansion of the universe 🔒 Pro 8 video(s)

Unit 3 Stars, black holes and galaxies

1 Life and death of stars 🔒 Pro 10 video(s) 2 Quasars and galactic collisions 🔒 Pro 3 video(s) 3 Stellar parallax 🔒 Pro 5 video(s) 4 Cepheid variables 🔒 Pro 3 video(s)

Unit 4 Earth geological and climatic history

1 Plate tectonics 🔒 Pro 8 video(s) 2 Seismic waves and how we know earth's structure 🔒 Pro 4 video(s) 3 Earth's rotation and tilt 🔒 Pro 7 video(s) 4 Moon phases and eclipses 🔒 Pro 2 video(s)

Unit 5 Life on earth and in the universe

1 History of life on earth 🔒 Pro 3 video(s) 2 Humanity on earth 🔒 Pro 6 video(s) 3 Measuring age on earth 🔒 Pro 4 video(s) 4 Life in the universe 🔒 Pro 5 video(s)