Where does this come from, and can I check it?

Without air or gas particles sound waves cannot propagate through the cosmic vacuum. The figure is taken from NASA Science, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a space fact?

Yes. It sits on the Space shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Space is completely silent because sound needs a medium to travel

Without air or gas particles sound waves cannot propagate through the cosmic vacuum

Sound is a mechanical wave that requires a physical medium such as air, water or solid material to vibrate and travel. Because space is an almost perfect vacuum containing extremely sparse matter, sound waves cannot travel between celestial bodies, making outer space completely silent to human ears.

97815 letron church of the silent monastery PikiWiki Israel — israel zeller ישראל זלר · CC BY 2.5 · licence · source

Where this comes from

NASA Science

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Tags: vacuum, sound, physics

Space is completely silent because sound needs a medium to travel: the short answers

Where does this come from, and can I check it?: Without air or gas particles sound waves cannot propagate through the cosmic vacuum. The figure is taken from NASA Science, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a space fact?: Yes. It sits on the Space shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.