仙王座δ（δ Cep/ 仙王座δ）是仙王座内距离地球大约891光年的一对联星。
只要恰当地控制粒子束的照射时间，该恒星将有效地成为一台调频电台——以“造父变星”的脉冲为基础载波向宇宙广播。
Time the beam right and the star could be turned, in effect, into an FM transmitter-broadcasting to the universe on the underlying carrier-wave of the Cepheid's pulsation.
且由于在另一个星系中的单颗“造父变星”的亮度就足于使其被观测到，所以它们是测算类似星系距离的首选工具。
And, since individual Cepheids are bright enough to be seen in other galaxies, they were the first tool used to estimate the distances to such galaxies.
另一种标准烛光是一种叫做造父变星的恒星。
Another type of standard candle is a type of star called a Cepheid variable.
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