How can we know so much about other galaxies? What are they made of? How big are they? How far away are they from Earth?

“Want to know the secrets of the universe? Just follow the light.”

These two TED Eds from Harvard University’s Yuan-Sen Ting give us a more detailed glimpse of how astrophysicists see the universe: Above, How do we study the stars? Below, Light seconds, light years, light centuries: how do we measure extreme distances into space?

There are so many effective ways to explain how we observe and learn more about the universe. Watch more excellent explanations: How do we measure the universe? How can we know anything about distant exoplanets? The Hubble Ultra Deep Field in 3D and Spectroscopy of Stars.

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