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MLA Full: "When The Stars Turned On | Crash Course Pods: The Universe #4." YouTube, uploaded by CrashCourse, 5 June 2024,
MLA Inline: (CrashCourse, 2024)
APA Full: CrashCourse. (2024, June 5). When The Stars Turned On | Crash Course Pods: The Universe #4 [Video]. YouTube.
APA Inline: (CrashCourse, 2024)
Chicago Full: CrashCourse, "When The Stars Turned On | Crash Course Pods: The Universe #4.", June 5, 2024, YouTube, 58:12,
"Is free will still in the equation?"

In this episode, the universe begins to become visible to itself. Dr. Katie Mack teaches John Green about the moment the stars turned on, while John seeks to answer one question... do humans matter to the universe?

Head to to get your free life insurance quotes and see how much you could save.

0:00 - Introduction
0:55 - Do humans matter to the universe?
12:52 - The Stars Turned On
19:28 - Reionization
38:35 - Redshift and Radio Telescopes
48:10 - Katie expands on her work
53:01 - Being Suitably Small
56:22 - Conclusion

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