Usar "variable star" en una oración

1. lives of variable stars

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2. The collection and study of variable star data

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3. Variable stars are stars that vary in brightness, or magnitude

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4. variables are one type of pulsating variable stars

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5. variable stars - including Cepheids - are plotted as the apparent

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6. The light curve for the Cepheid variable star X Cyg (located in the

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