The Black Hole That Switched Back On

About this episode

This episode discusses the observation of a rare changing-look active galaxy and its implications for understanding black hole behavior.

Astronomers using the eROSITA telescope have observed a rare “changing-look” active galaxy over a billion light-years away. The galaxy HE 1237−2252 dramatically faded in X-rays before unexpectedly returning to its original brightness, revealing a supermassive black hole rapidly changing its feeding activity in real time. Scientists believe the phenomenon was driven by powerful thermal waves moving through the black hole’s accretion disk rather than obscuring dust clouds. The discovery offers an extraordinary opportunity to study how black holes evolve, reignite, and influence the energetic life cycles of distant galaxies. Thank you for listening to Bedtime Astronomy — your guide to the cosmos. New episodes on space exploration, NASA missions & the latest astronomy breakthroughs. This episode includes AI-generated content.

People in this episode

Host: Synthetic Universe

Topics covered

• black holes
• active galaxies
• X-ray astronomy
• accretion disks
• galaxy evolution

Keywords

• black hole
• changing-look galaxy
• eROSITA telescope
• X-rays
• accretion disk
• thermal waves
• galaxy evolution

Mentioned in this episode

Organizations: eROSITA

Places: HE 1237−2252, a billion light-years away

More episodes of Bedtime Astronomy

• How Supernova Dust Changed the Early Universe · June 12, 2026 · 58 min
• The Future of Humanity May Exist Inside Giant Space Cylinders · June 10, 2026 · 38 min
• Scientists Created a New Way to Detect Alien Life · June 9, 2026 · 37 min
• James Webb May Have Found One of the Universe’s First Galaxies · June 8, 2026 · 41 min
• Astronomers Just Watched Space Distort Light in Real Time · June 7, 2026 · 30 min
• NASA’s Nuclear Rocket Could Change Mars Missions Forever · June 6, 2026 · 15 min