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Birthday · July 1, 1995

The Hooker Telescope on Mt. Wilson

July 1, 1995

Some stars end in silence, some in fire, and some leave behind the raw materials for birthdays.

The Hooker Telescope on Mt. Wilson

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APOD published July 1, 1995. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

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The Hooker Telescope on Mt. Wilson

Original APOD · July 1, 1995

July 1, 1995 The Hooker Telescope on Mt. Wilson Picture Credit: Mount Wilson Observatory Explanation: In the 1920s, pictures from the Hooker Telescope on Mt. Wilson fundamentally changed our understanding of the cosmos. Astronomer Edwin Hubble, using photographs he took with this telescope, demonstrated that the objects his contemporaries called "spiral nebulae" were actually huge systems of stars - spiral galaxies, similar to our own Milky Way galaxy but incredibly distant. Prior to Hubble's work it was argued that the spiral nebulae were mere clouds of gas and that they, along with everything else in the universe, were contained in our own galaxy. The Hooker Telescope mirror is 100 inches in diameter which is nearly the size of the mirror of the orbiting Hubble Space Telescope named in Hubble's honor. The Mount Wilson Observatory offers a "virtual walking tour" of this historic telescope. For more information see Mount Wilson Observatory Historical Image Archives We keep an archive of Astronomy Pictures of the Day. Astronomy Picture of the Day is brought to you by Robert Nemiroff and Jerry Bonnell . Original material on this page is copyrighted to Robert J. Nemiroff and Jerry T. Bonnell.

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