Mount Wilson Observatory History

In 1904, the Mount Wilson Observatory was founded  by George Ellery Hale under the auspices of the Carnegie Institution of Washington. In that year, Hale brought the Snow Solar Telescope from Yerkes Observatory in southern Wisconsin to the sunnier and steadier skies of Mount Wilson to continue his studies of the Sun. With a small cadre of Yerkes scientists and engineers accompanying him, Hale started what would become the world’s foremost astronomical research facility. Hale put such importance on studying the Sun, that it was called the Mount Wilson Solar Observatory for the first decade and a half. In 1919, soon after the largest telescope in the world, the 100-inch, went into service photographing the stars and nebulae, the word “Solar” was dropped. Hubble used the 100-inch to make his great discoveries–that we are just one of many galaxies in an ever expanding Universe. This telescope lead directly to our current understanding of our origins, the Big Bang model. 

A timeline retrospective of the Observatory’s first century is available here.

Our founder

George Ellery Hale (1868-1938) founded the Observatory in 1904 and directed it until his retirement in 1923.

Building the Observatory

The extraordinary story of the challenges & accomplishments of the early pioneering years of a remote and isolated mountaintop observatory.

Exploring History & Science

The scientific process of astronomy begun more than a century ago at Mount Wilson continues today around the world.

A Deeper Dive With Two Mount Wilson Observatory Directors

George Ellery Hale was a prolific writer of books and articles aimed at the educated public in whom he wanted to instill the thrill of modern astronomy. Here are a few of his articles reporting on various aspects of progress at the young Mount Wilson Observatory:

Walter S. Adams was brought to Mt. Wilson from Yerkes at the outset of George Ellery Hale’s westward move. Adams subsequently succeeded Hale as MWO Director in 1923. The following are articles written by Adams that deal with Mount Wilson events and people: