No Boom

No Boom

From StarDate by Billy Henry

May 7, 2026 · 2 min

About this episode

The episode discusses a massive star in the Andromeda Galaxy that collapsed into a black hole instead of exploding as a supernova.

A massive star in the Andromeda Galaxy might have tried to blow itself to bits, but it failed. Instead, almost the entire star collapsed to form a black hole about five times the mass of the Sun. Astronomers discovered the possible misfire while combing through observations by NeoWise, a space telescope that wrapped up its work a couple of years ago. They found an object that brightened dramatically at infrared wavelengths, which are invisible to the human eye, then slowly faded again. Earlier observations at visible wavelengths showed a supergiant star, perhaps a hundred thousand times as bright as the Sun. But as the infrared peaked and faded, the visible light faded completely – the star simply vanished. The astronomers concluded that the event was a failed supernova. The star stopped producing nuclear reactions in its core, so the core collapsed. A shockwave plowed through the star’s outer layers, blasting their gas outward. In most cases, such a shockwave creates a titanic explosion – a supernova. But this blast wasn’t powerful enough to overcome the core’s gravitational pull. So almost all the gas fell back onto the core, making it massive…

People in this episode

Host: Billy Henry

Topics covered

  • black holes
  • supernova
  • astronomy
  • stellar evolution
  • Andromeda Galaxy

Keywords

  • black hole
  • supernova
  • Andromeda Galaxy
  • NeoWise
  • stellar collapse

Mentioned in this episode

Organizations: NeoWise

Places: Andromeda Galaxy

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