Cosmology and astronomy: Scale of distance to closest stars

The nearest stars to our solar system, are located in the Alpha Centauri system. The two main stars are Alpha Centauri A and Alpha Centauri B, which are approximately 4.3 light years away from Earth. The third star in the Alpha Centauri system, Proxima Centauri, is actually the closest star to our solar system at approximately 4.2 ​lightyears away from Earth. 

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.

Scale of earth, sun, galaxy and universe

The Earth is huge, but it is tiny compared to the Sun (which is super huge). But the Sun is tiny compared to the solar system which is tiny compared to the distance to the next star. Oh, did we mention that there are over 100 billion stars in our galaxy (which is about 100,000 light years in diameter) which is one of hundreds of billions of galaxies in just the observable universe (which might be infinite for all we know). Don't feel small. We find it liberating. Your everyday human stresses are nothing compared to this enormity that we are a part of. Enjoy the fact that we get to be part of this vastness!

Topic: Science

Learn about all the sciences, from physics, chemistry and biology, to cosmology and astronomy, across hundreds of videos, articles and practice questions.