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Black Hole Star: The Star That Shouldn't Exist: summary
Black Hole Star: The Star That Shouldn't Exist
- Today's biggest stars top out around 300 solar masses. A black hole star could reach 10 million.
- Normal stars blow away their birth cloud once fusion starts, which limits how big they get.
- In the dense early universe, gas kept piling on so fast that some stars grew far past that limit.
- The pressure inside the star forces matter into the black hole much faster than a black hole could normally eat.
- Some supermassive black holes already had 800 million solar masses within 690 million years of the Big Bang, which is hard to explain without a shortcut like this.
What is a black hole star?
A hypothetical giant star from the early universe, up to 10 million times the mass of the Sun, with a black hole growing at its center. The star was so massive that even the supernova that formed the black hole couldn't blow it apart. The black hole then ate the star from the inside for millions of years before bursting out. If they existed, they could explain how supermassive black holes got so big so early.
Actionable
- Follow James Webb Space Telescope news on the earliest galaxies.
- Compare this video with Kurzgesagt's black hole bomb video for how spin and accretion work.
- Look up how supermassive black holes are measured to see why their size puzzles scientists.
Lessons
- Conditions in the early universe allowed things that can never happen again.
- Big mysteries often push scientists toward bold explanations that can later be tested.
- A balance of forces explains a lot about stars, from small ones to giants.
Quick answer
Kurzgesagt posted this video on Dec 15, 2022. Here's our summary in our own words: the answer to the title, a verdict, 5 takeaways, and Actionable and Lessons tabs.
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Watch on YouTube: Black Hole Star: The Star That Shouldn't Exist
Channel: Kurzgesagt. Published Dec 15, 2022. About 10 minutes.
What they recommend
Nothing to do here except watch for news from the James Webb Space Telescope, which the video says may be able to spot signs of these stars.
Quotes from the video
- “Black hole stars may have been the largest stars to ever exist.”
- “Basically, black holes put a lot of food on the table and only nibble at it.”
- “But in this case, the star survives its own death.”
A note on this summary
This page reports what the video says, in our own words. Quotes are copied word for word from the video's transcript. Views are as of Oct 30, 2026.
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FAQ: questions people ask
What is a black hole star?
A theoretical early universe star so massive that a black hole formed at its core without destroying it, then fed on the star from inside.
Do black hole stars exist?
They're hypothetical. The video says the James Webb Space Telescope may find evidence for them.
Is the video worth watching?
Good value given. Short, clear and visually stunning.
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