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 ...
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 ...
On 1 January 1925, US astronomer Henry Norris Russell made a startling announcement to the American Astronomical Society in Washington DC: observations by fellow astronomer Edwin Hubble showed that ...
For humans, the most important star in the universe is our sun. The second-most important star is nestled inside the Andromeda galaxy. Don't go looking for it—the flickering star is 2.2 million ...
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 ...
It’s not often that telescopes suspended in space have landmark birthdays like this one. Launched on April 24, 1990, NASA’s Hubble Space Telescope has orbited at about 320 miles above Earth’s surface, ...