Was the Milky Way a Quasar?
Summary
This episode explores the discovery of the Fermi bubbles, massive gamma-ray structures extending from the Milky Way's center, which reveal that our galaxy experienced a violent active galactic nucleus phase just a few million years ago. The host discusses how this event likely resulted from a combination of Sagittarius A* accreting matter and a subsequent starburst, and notes that recent radio observations suggest similar, smaller outflows are occurring now.
Topics discussed
Sponsorships: Progressive and Anthropic
Introduction: The violent past of the Milky Way
Active Galactic Nuclei and Quasars
Discovery of the Fermi Bubbles
How the Fermi Bubbles were hidden
Sponsorships: Progressive and Anthropic
Sponsorship: Lincoln Wishlist
Energy source and age of the Fermi Bubbles
Hypothesis 1: Starburst and Supernovae
Hypothesis 2: Black Hole Activity
Combining theories: Jets and Starbursts
Sponsorships: Progressive and Anthropic
Sponsorship: Lincoln Rejuvenate
The combined mechanism explained
Discovery of smaller Radio Bubbles
Implications for Earth and future activity
Promotion: PBS Terra and Antarctic Extremes
Q&A: Age of Earth and Claire Patterson
Q&A: Concordia Diagram explanation
Sponsorships: Progressive and Anthropic
Sponsorship: Lincoln Rejuvenate
Q&A: Good Omens quote and Earth's zodiac sign
Sponsorships: Progressive and Anthropic
Sponsorship: Brooks Brothers
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