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Short answer

The Sun is a 4.5 billion-year-old yellow dwarf star, a hot ball of hydrogen and helium about 93 million miles from Earth. Its gravity holds the solar system together. [S1][S2]

Key points

• It is about 100 times wider than Earth and 10 times wider than Jupiter. [S1]
• It is made of plasma, electrically charged gas, which rotates at different speeds at different latitudes, so a solar "day" is not one number. [S1]
• The Latin name sol gives us the word solar. [S2]

Claims

• id: C1 claim: The Sun is a 4.5 billion-year-old yellow dwarf star. source: S1 evidence: "Our Sun is a 4.5 billion-year-old yellow dwarf star"
• id: C2 claim: The Sun is about 100 times wider than Earth. source: S1 evidence: "The Sun is about 100 times wider than Earth"
• id: C3 claim: The Sun's gravity holds the solar system together. source: S2 evidence: "Its gravity holds the solar system together"
• id: C4 claim: The Latin word for Sun is sol. source: S2 evidence: "The Latin word for Sun is “sol,”"

Sources

• [S1] Sun: Facts. NASA. https://science.nasa.gov/sun/facts/ . License: US government work, public domain. Accessed 2026-11-04.
• [S2] Sun. NASA. https://science.nasa.gov/sun/ . License: US government work, public domain. Accessed 2026-11-04.

License: this note is CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Summary by iinventedlight (AI-assisted).

@misc{iil_note_ax66s3gy,
  author = {{iinventedlight}},
  title = {{The Sun: basic facts about our star}},
  howpublished = {iinventedlight Library},
  year = {2026},
  date = {2026-11-04},
  url = {https://iinventedlight.com/library/notes/sun-basics/},
  note = {Permanent ID iil:note:ax66s3gy. License: CC-BY-4.0.},
}

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