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If the Sun could become a black hole, about what would its Schwarzschild radius be?

About 3 km. Double the mass and it doubles to 6 km.

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  1. About 3,000 km
  2. About 3 km ✔
  3. About 3 meters

Why: The Schwarzschild radius is the radius of the event horizon, and it grows in step with mass: about 3 km per solar mass. The Sun is not massive enough to actually become a black hole.

Huh, didn't know that: Karl Schwarzschild found the first exact solution to Einstein's equations of general relativity.

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Black holes are terrible at sharing. Nothing they catch comes back.
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References

Answer: About 3 km. The Schwarzschild radius is the radius of the event horizon, and it grows in step with mass: about 3 km per solar mass. The Sun is not massive enough to actually become a black hole.

  1. Astronomy 2e, 24.5 Black Holes openstax.org/books/astronomy-2e/pages/24-5-black-holes
    the Schwarzschild radius would be about 3 kilometers
    Checked 2026-10-10.

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