How did a Cepheid variable star help Edwin Hubble prove the Andromeda Nebula was a galaxy? Roger Brady San Quentin, California Cepheids are rare variable stars with periods ranging from about 1 to 120 ...

Cepheid variables are a type of star that undergo regular pulsations. The length of a Cepheid’s pulsations is always related to its intrinsic, or absolute, brightness in a simple way: The longer its ...

An image of the Cepheid variable star RS Puppis. The most accurate observation to date of distant stars that periodically change in brightness may spark a rethink of the rate at which the universe ...

On the night of Oct. 5 to 6, 1923, Edwin Hubble discovered a new star — and revealed the utter vastness of the universe. Hubble was looking at the cosmos with the 100-inch Hooker telescope at the ...

ABOVE: This composite photo by NASA, ESA, the Hubble Heritage Team and R. Gendler shows the Andromeda Galaxy. The Cepheid variable star V1 is indicated with an arrow, and four inset images show the ...

Taking advantage of the very high spatial resolution provided by the Very Large Telescope Interferometer, a team of French and Swiss astronomers [1] has measured directly the change in angular ...

Astronomers from the University of Warsaw, Poland and elsewhere have detected a new classical Cepheid variable star. The newfound star, which received designation OGLE-GD-CEP-1884, has the longest ...

Cepheid stars have predictable brightness changes linked to their periods. This period-brightness relationship lets astronomers calculate a Cepheid's distance. Hubble found a Cepheid in the Andromeda ...