Background

George Willis Ritchey was born on December 31, 1864, at Tuppers Plains, Meigs County, Ohio, the second of five sons of James and Eliza (Gould) Ritchey. His father, a native of Ireland, had migrated to the United States during the potato famine of 1846. A cabinetmaker by trade, he was also an amateur astronomer, owner of an 8 1/2-inch reflecting telescope made by John A. Brashear. Thus George Ritchey was inspired early with a love of astronomy. He also possessed a manual dexterity and an inventive ability that later proved invaluable in his grinding of telescope mirrors and design of mountings.

Education

Ritchey attended public school near Pomeroy, a mining community in southeastern Ohio, until, in 1880, the family moved to Cincinnati. There he took courses (1883-84, 1886-87) at the University of Cincinnati.

Career

After moving to Chicago in 1888, Ritchey became head of the woodworking department at the Chicago Manual Training School. There, while working on the construction of a 2-foot telescope mirror, he met the young astronomer George Ellery Hale.

In 1896 Hale, now director of the University of Chicago's Yerkes Observatory, brought Ritchey to its staff, at first as head of the optical laboratory and later as superintendent of instrument construction. The 40-inch refracting telescope at Yerkes, the largest in the world, had originally been designed for visual observation only. By means of a color screen and isochromatic plate, Ritchey turned it into a camera, and with it he took sharp, detailed photographs of the moon, planets, and planetary nebulae that have rarely been equaled in quality.

At Yerkes also, his 24-inch reflector, with a skeleton tube and a design notable for its efficiency, was mounted; with it, he took plates that helped prove the superiority of the reflector in the photography of faint stars, star clusters, and nebulae. There, too, he ground the mirror for a 60-inch reflector, for which Hale's father, William Hale, had donated the funds.

From 1901 to 1906 he was on the astronomy faculty at the University of Chicago, and in 1904 he was elected an associate of the Royal Astronomical Society. In 1904, when the Mount Wilson Observatory was founded near Pasadena, California, under Hale's direction, Ritchey joined the staff as superintendent of construction (until 1909), then took charge of the optical shop. In 1906, again at the request of Hale, Ritchey became the head of instrument construction at another new observatory, Mt. Wilson.

He worked first with Hale on the auxiliary instruments and design of the Snow horizontal reflecting telescope. He continued work on the 60-inch reflector, already ground and partly polished at Yerkes, and perfected a method of parabolizing that eliminated the need for any handwork.

The telescope, with a fork-type mounting and "mechanical flotation" support system of his design, was set up on Mount Wilson in 1908 and was soon proving its superiority over any reflector yet built.

In 1917 Ritchey's chance discovery of a nova in the galaxy NGC 6946, on a plate made with the 60-inch reflector, followed by the discovery of similar objects by other astronomers, played a key role in the interpretation of the nature of galaxies and measurement of their distances.

In 1908 the disc for a 100-inch telescope, ordered by Hale, arrived from the Saint Gobain company in France. It contained numerous bubbles: Ritchey was sure it was a failure. When it was finally accepted, he undertook with deep pessimism the slow, tedious process of grinding that with the help of two able assistants, led to its completion in 1917.

He worked also on the initial design of the mounting, later greatly modified. He was, however, convinced that the future of large telescopes lay in cellular mirrors and in a form of mounting which later, as the Ritchey-Chrétien aplanatic system (with a tube length considerably less than the focal length), was applied to various telescopes, including one at the Pic du Midi in the French Pyrenees and a 40-inch reflector at the United States Naval Observatory in Flagstaff, Arizona. When these and other ideas were not adopted at Mount Wilson, Ritchey's sense of isolation and persecution grew.

During World War I, Ritchey trained over 100 people to make optical parts for gunsights for the United States Ordnance Department. At the end of the war, following a bitter controversy at Mt. Wilson, Ritchey was dismissed from the staff because of a health problem and for allegedly exceeding his authority. He spent the next five years at his private laboratory in California, continuing the work he had started at Mt. Wilson, particularly on the development of cellular mirrors.

In 1924, the year he was elected an associate member of the Royal Astronomical Society, Ritchey became director of the Dina Optical Laboratory of the Paris Observatory. His experiments there included the design of a series of "super" tower telescopes with interchangeable mirrors, all of the cellular type.

After leaving the Paris Observatory, he moved in 1931 to the Naval Observatory in Washington, D. C., where for the next five years he continued his research in astronomical photography. In 1936 he retired to his citrus ranch in Azusa, California.

Achievements

• Ritchey's greatest achievement was in becoming one of the most prominent optical instrument makers of his time, who not only fashioned some of the largest instruments of his era but also used them to make important astronomical contributions. Moreover, his meticulous care in observing was almost unequaled. He demonstrated the similarity between the dark lanes in the Milky Way and the Andromeda nebula (M31), and he resolved the outer portions of M31 into individual stars. In 1917 Ritchey photographed novae (and supernovae) in M31, thereby facilitating the first reasonably accurate measurement of the distance to a spiral nebula.
  
  While in Paris, Ritchey, with Henri Chretien, perfected a design for an aplanatic reflector. Upon completion of the first such telescope in 1930, Ritchey was made a Knight of the Legion of Honor.
  
  Ritchey' was awarded the Prix Jules Janssen in 1924, which is the highest award of the Société Astronomique de France. Craters on Mars and the Moon were named in his honor.

Works

More photos

• book

  • The Astrophysical Journal

    (volume 12)

    1900
  • Astronomical Photography with the Forty-Inch Refractor and the Two-Foot Reflector of the Yerkes Observatory 1904
  • On The Construction Of A Silvered Glass Telescope: Fifteen And A Half Inches In Aperture, And Its Use In Celestial Photography 1864
  • On the modern reflecting telescope 1904

• design

  • Ritchey 24" reflecting Telescope

    (With the existing 40-inch refractor and a new 24-inch ref...)

    1890

Views

Ritchey was a visionary in the field of astrophysics whose ideas were considered radical for his time. At his core, he was a photographer, and he saw the telescope as a lens through which to take ever better celestial photographs. His influence on astronomical research was profound and this archive is a rich offering of his life’s work.

Quotations: "As cathedrals and churches, as universities and schools are dedicated to God, " Ritchey wrote, "so these super-telescopes will be dedicated and soon."

Membership

George Ritchey was a member of the French Astronomical Society. In 1924 he was elected an associate member of the Royal Astronomical Society.

• 

  Royal Astronomical Society , United Kingdom

  1924 - 1945

Personality

On the design of a telescope, the grinding of a mirror, the taking and developing of a plate, Ritchey would spend endless hours, never satisfied until the result was as near perfection as possible. Yet many of his plates, while beautiful, are limited in scientific value because he failed to record the date and time of observation or scribbled them on the dome door, where an irate carpenter later planed them off and painted them over. With the soul of an artist, he had, as a colleague put it, "the temperament of a thousand prima donnas."

Physical Characteristics: In his last years, Ritchey acquired a bad case of chronic myocarditis from which he died at the age of eighty-one.

Interests

• photography

Connections

On April 8, 1886, Ritchey married Lillie M. Gray of Cincinnati, by whom he had two children, Willis and Elfreda.

Father:

James Ritchey

Mother:

Eliza (Gould) Ritchey

Wife:

Lillie M. Gray

Son:

Willis Ritchey

Daughter:

Elfreda Ritchey

collaborator:

Henri Jacques Chrétien

Ritchey coinvented the Ritchey-Chrétien (R-C) reflector telescope along with Henri Chrétien.

colleague:

George Hale

Ritchey worked closely with George Ellery Hale, first at Yerkes Observatory and later at Mt. Wilson Observatory.

References

• Dictionary of Scientific Biography Volume 11
  1975