1. In the 1920s Edwin Hubble observed that distant galaxies look redder than nearby ones.

2. Let's stick with Edwin Hubble for a second.

3. Named for Edwin Hubble, it was built under NASA supervision and deployed on a 1990 space-shuttle mission.

4. Edwin Hubble was the first person to use the Hale Telescope.

5. However, twelve years later, Edwin Hubble showed that universe was not static, but expanding in space.

6. American astronomer Edwin Hubble first developed a classification system in the 1930s, known as the Hubble Sequence, which divides galaxies into two main types: spirals, and ellipticals.

7. Edwin Hubble discovered that distant galaxies are moving away from us.

8. Then, a decade or so later, Edwin Hubble discovered that the universe is expanding after all.

9. By measuring the optical spectra of distant galaxies, Edwin Hubble noted that the velocity at which a galaxy moves away from the Earth increases proportionally to its distance from the Earth.

10. Then, in 1929, Edwin Hubble published his observations showing that the universe is expanding.

11. Edwin Hubble changed our ideas about the universe and how it developed.

12. It's named after Edwin Hubble, a pioneering American astronomer who furthered our understanding of other galaxies and demonstrated that the universe is continually expanding.

13. Edwin Hubble observed that all galaxies except the closest ones to us — which are those in our local group of galaxies — are moving away.

14. Edwin Hubble was about to make astronomy's greatest breakthrough of the century.

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15. Theorists, including Albert Einstein, had been analyzing the dynamics of an expanding universe even before Edwin Hubble observed it in 1929.

16. Today, Richard Rael and Tony Riggs tell the story of American astronomer Edwin Hubble.