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AhaBulb: Stuff Everyone Should Know · ahabulb.com/astro-universe-age

About how old is the universe?

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  1. 4.6 billion years
  2. 138 billion years
  3. 13.8 billion years

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References

  1. Astronomy 2e Chapter 29 Summary openstax.org/books/astronomy-2e/pages/29-summary Checked 2026-10-10.

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