Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.astronomy.com/magazine/ask-astro/2015/08/astronomical-distances
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How do astronomers use Cepheid variables to measure distances? | Astronomy.com
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FROM THE October 2015 ISSUE

How do astronomers use Cepheid variables to measure distances?

Richard Lynch, Essex Junction, Vermont
Published: Monday, August 24, 2015
RELATED TOPICS: VARIABLE STARS
VISTA views the Trifid Nebula and reveals hidden variable stars.
The simple answer is that the intrinsic brightness of these variable stars is strongly tied to their period. This is the famous period-luminosity relationship discovered by Henrietta Leavitt more than a century ago.

Astronomy magazine subscribers can read the full answer for free. Just make sure you're registered with the website.

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