66 - When Space Was Filled With Music

Shortly after the Big Bang, space was densely packed with enough stuff for sound to travel through it. What was producing sound in this era, and how can we hear it today?

Todays episode is sponsored by the International Space Station. Join the ISS National Laboratory this August in Seattle at the 12th annual ISS Research and Development Conference. Visit ISSconference.org (issconference.org)to register now.
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