SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/aero-mercury-smallest-planet

Which planet is the smallest in our solar system?

Mercury is the smallest planet.

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  1. Mars
  2. Venus
  3. Mercury ✔

Why: Mercury is only a little larger than Earth's Moon. It is also the planet nearest the Sun.

Huh, didn't know that: Like Earth, Mercury has a central core, a rocky mantle and a solid crust.

The dad joke
Mercury entered the tiny planet contest and won big.
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References

Answer: Mercury. Mercury is only a little larger than Earth's Moon. It is also the planet nearest the Sun.

  1. Mercury Facts science.nasa.gov/mercury/facts
    Mercury is the smallest planet in our solar system and nearest to the Sun.
    Checked 2026-10-10.

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