SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/aero-light-year-distance

What does a light-year measure?

Distance, specifically how far light travels in one year.

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  1. A star's age
  2. A telescope's brightness
  3. A very large distance ✔

Why: A light-year is not a unit of time in astronomy. It is the enormous distance light crosses during one year.

Huh, didn't know that: One light-year is about 5.88 trillion miles.

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A light-year sounds late, but it is really just far out.
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References

Answer: A very large distance. A light-year is not a unit of time in astronomy. It is the enormous distance light crosses during one year.

  1. What Is a Light-Year? science.nasa.gov/exoplanets/what-is-a-light-year
    Light-year is the distance light travels in one year.
    Checked 2026-10-10.

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