What are the Fermi Bubbles?

Massive gamma ray structures above and below Milky Way.

Was the Milky Way a Quasar?

PBS Space Time・2 minutes read

The Milky Way galaxy, once thought to have a calm history, has revealed violent past events, including the discovery of massive gamma ray structures called the Fermi Bubbles. These bubbles, originating from the central black hole, play a crucial role in understanding the galaxy's evolution and potential future events, emphasizing the importance of monitoring Sagittarius A* for insights into the Milky Way's activity.

Insights

The Milky Way, despite its overall calm history, contains a massive black hole at its center, along with smaller black holes, hot gas clouds, and massive stars, hinting at a complex and dynamic internal structure.
The discovery of the Fermi Bubbles, massive gamma ray structures formed through Inverse Compton Scattering, suggests a violent past for the Milky Way, with energy equivalent to 100,000 supernova explosions, potentially originating from a mini AGN phase near the central black hole.

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Summary

00:00

"Violent Past and Potential Future of Milky Way"

The Milky Way galaxy has a relatively calm history compared to other galaxies, but recent discoveries suggest a violent past that could recur.
Despite the calmness of the Milky Way, it houses an enormous black hole at its center, along with smaller black holes, hot gas clouds, and massive stars.
The Fermi Bubbles, massive gamma ray structures extending 25,000 light years above and below the Milky Way, were unexpectedly discovered.
The Fermi Bubbles were hidden by the gamma ray glow of the Milky Way, but their high-energy gamma rays distinguished them.
The Fermi Bubbles were formed through Inverse Compton Scattering, involving extremely energetic electrons interacting with light.
The energy contained in the Fermi Bubbles is equivalent to that released by 100,000 supernova explosions.
The Fermi Bubbles likely originated from a mini AGN phase triggered by gas influx or a star's proximity to the black hole, leading to star formation and supernova explosions.
Recent studies using the MeerKAT telescope array discovered radio bubbles near the Galactic core, likely originating from the central black hole and magnetic field-accelerated electrons.
The X-ray activity of the Milky Way's central black hole has been increasing, hinting at potential future events, although Earth's atmosphere absorbs most gamma rays.
While the creation of new Fermi Bubbles may not be imminent, monitoring the activity of Sagittarius A* provides insights into its influence on the Milky Way.

14:29

"Concordance diagram reveals Earth's true age"

In a crystal, the concordance diagram shows a linear correlation due to cracks, with lead-206 to uranium-238 ratios on the Y-axis and lead-207 to U-235 on the X-axis following a curved line. The U-238 decays quickly in the first few billion years, then U-235 dominates later, creating the classic concordia curve.
Various historical claims on the Earth's age, from medieval Jewish scholars to Archbishop James Usher, are debunked, with the latter pinpointing the Earth's creation at 4004 B.C. on a Sunday at 9:00 A.M., which was proven incorrect due to a slight time discrepancy. Tasha Montgomery's zodiac reference is critiqued for overlooking the precession of the equinoxes, leading to the conclusion that Earth is a Taurus.