Membership

AHO members engage in various joint activities aligned with alliance objectives: astronomical site, asset, and data preservation; collaborative public engagement and media projects; STEM-focused outreach; and strategic collaboration on mature facility operations.

There are two types of membership: “Voting” and “Associate” (see Bylaws Article 3).

A. Voting/regular member criteria

  1. Be widely recognized as an astronomical observatory (i.e. individuals are not eligible to the regular members, but rather may be designated as Associate members, and potentially Special Delegates)
  2. Having been in existence for a minimum amount of time (e.g. be older than say ~50 – 70 years)
  3. Be widely recognized as having made historic and on-going contributions to one or more of the following:
    • astronomy, astrophysics, or closely related disciplines;
    • public engagement and/or information on astronomy or closely related disciplines;
    • and/or having notably served the public, national, or international interests through the application of astronomy or closely-related disciplines
  4. Attest to institutional objectives that are well-aligned with AHO stated objectives
  5. Maintain compliance with AHO Member criteria and responsibilities
  6. Have current active programs in astronomical research, public engagement in astronomy, or serve the public, national or international interests through the application of astronomy

B. Associate member criteria

  1. For organizations: Meet several of the organizational criteria listed above, or
  2. Be engaged either as an organization or an individual in activities that are closely aligned with AHO objectives such as:
    • The restoration, maintenance, curation. and/or stewardship of astronomy-related historical artifacts, practices, facilities, and/or data (e.g. photographic plates, observing logs)
    • Educational and/or public engagement activities that disseminate astronomy or related disciplines including methods and techniques
    • Philanthropic support of organizations or initiatives that align with AHO objectives
  3. For individuals: Be recognized as an individual who has made substantive contributions to AHO formation, organization, and/or objectives
  4. Maintain compliance with AHO Associate Member criteria and responsibilities

To nominate an institution or individual for membership, please use our contact form.

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Yerkes Observatory south façade (source)
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The 24-inch Clark Telescope at Lowell Observatory (Lowell Observatory/S.Gilbert)
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The Hale Telescope dome at Palomar Observatory (Palomar Observatory/Caltech)
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The 100-inch Hooker Telescope at Mt. Wilson Observatory (Mt. Wilson Observatory/D.Jurasevich)
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Aerial view of Griffith Observatory (source)
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The 36-inch Great Lick Refractor at Lick Observatory (UC Regents/Lick Observatory/C.Schodt)
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Aerial view of Castel Gandolfo, Vatican Observatory (source)
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Pic du Midi Observatory (Pic du Midi)
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The Otto Struve Telescope of McDonald Observatory at sunrise (University of Texas/Ethan Tweedie)
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The Judy and Stanley Frankel Detroit Observatory (University of Michigan)
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The Center of the Universe at the Dominion Astrophysical Observatory (FDAO)

Member Observatories

Detroit Observatory

est. 1854

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Detroit Observatory
est. 1854
Ann Arbor, MI, USA
University of Michigan

Third largest refracting telescope in the world (1857)

Fitz Refracting Telescope (0.32m, 1857)
Meridian Circle Telescope (1854)

Austin Edmister (assistant director)

Website History Visiting Support Exhibits Events

Dominion Astrophysical Observatory

est. 1918

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Dominion Astrophysical Observatory
est. 1918
Victoria, BC, Canada
National Research Council Canada

Second largest telescope in the world (1918)

Plaskett Telescope (1.8m reflector, 1918)
48-inch telescope (1.2m reflector, 1961)

Dennis Crabtree (vol-professional)

Website History Research
Visiting Observing Programs Events Tour

Griffith Observatory

est. 1935

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Griffith Observatory
est. 1935
Los Angeles, CA, USA
City of Los Angeles

The most viewed telescope in the world (> 8.4 million visitors)

12-inch/9½-inch telescopes (0.3m/0.25m refractors, 1935/55)
Coelostat and Solar Telescopes (1935)

Ed Krupp (director)

Website History Visiting Observing Programs Exhibits Events

Lick Observatory

est. 1888

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Lick Observatory
est. 1888
Mt. Hamilton, CA, USA
University of California Observatories

Largest refractor in the world (1888)
The world's first permanently occupied mountain-top observatory

36-inch James Lick ("Great Lick") Refractor (0.9m, 1888)
36-inch Crossley Reflector (0.9m, 1879/1896)
20-inch Carnegie Double Astrograph (0.5m refractors, 1941)
22-inch Tauchmann Reflector (0.5m, 1954)
120-inch Shane Telescope (3m reflector, 1959)
Coudé Auxiliary Telescope (0.6m reflector, 1969)

Matthew Shetrone (deputy director)

Website History Research
Visiting Observing Programs Tour Live Cams Archives Events

Lowell Observatory

est. 1894

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Lowell Observatory
est. 1894
Flagstaff, AZ, USA

Discovery of Pluto (1930)

24-inch Clark Telescope (0.6m refractor, 1896)
13-inch A. L. Lowell Astrograph (0.3m refractor, 1929)

W. Lowell Putnam (trustee)

Website History Research
Visiting Stargazing Programs Exhibits Archives Events News

McCormick Observatory

est. 1885

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McCormick Observatory
est. 1885
Charlottesville, VA, USA
University of Virginia

Second largest refractor in the world (with USNO, 1885)

26-inch refracting telescope (0.65m, 1885)

Steve Majewski (chair)

Website History Visiting Observing Support Exhibits

McDonald Observatory

est. 1939

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McDonald Observatory
est. 1939
Fort Davis, TX, USA
University of Texas

Second largest telescope in the world (1939)
Third largest telescope in the world (1968)

Otto Struve Telescope (2.1m reflector, 1939)
Harlan J. Smith Telescope (2.7m reflector, 1968)
0.8m telescope (reflector, 1970)
0.9m telescope (reflector, 1956)

Katie Kizziar (asst. director for education & outreach)

Website Research Visiting Observing Programs Media Live Streams News

Mt. Wilson Observatory

est. 1904

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Mount Wilson Observatory
est. 1904
Mt. Wilson, CA, USA
Mount Wilson Institute

Largest telescopes in the world (1908 and 1917)
Discovery of the cosmic expansion

100-inch Hooker Telescope (2.5m reflector, 1917)
60-inch telescope (1.5m reflector, 1908)
60-ft (18m) Snow Solar Telescope (1905)
150-ft (46m) solar tower (1912)

Timothy Thompson (science director)

Website History Visiting Observing Programs Events Live Cams Tour

Palomar Observatory

est. 1948

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Palomar Observatory
est. 1948
Palomar Mountain, CA, USA
Caltech

Largest telescope in the world (1949)
Largest Schmidt in the world (1948)
Palomar sky surveys (1958 and 2000)
Discovery of quasars (1963)
Discovery of Eris (2005) and other TNOs

200-inch Hale Telescope (5m reflector, 1949)
48-inch Samuel Oschin Telescope (1.2m Schmidt, 1948)
18-inch telescope (0.46m Schmidt, 1936)
60-inch telescope (1.5m reflector, 1970)

Andy Boden (deputy director)

Website History Research Visiting Tour Exhibits Live Cams Archives News

Pic du Midi Observatory

est. 1878

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Pic du Midi Observatory
est. 1878
Pic du Midi de Bigorre, France
Paul Sabatier University (Toulouse III)

World's first high-mountain observatory
Formally discredited Martian canal theory
Mapped the surface of the Moon for the Apollo missions
Detailed Venus and Mars atmospheric studies
Discovery of Saturn's moon Helene


Rémi Cabanac (science director)

Website 1 Website 2 History Research Visiting Stargazing Programs Exhibits Live Cams News Events

Sommers-Bausch Observatory

est. 1953

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Sommers-Bausch Observatory
est. 1953
Boulder, CO, USA
University of Colorado

24-inch Boller & Chivens telescope (0.6m reflector, 1973)
Heliostat (1973)

Rose Smith (observatory manager)

Website History Visiting Programs Live Cams Events

Van Vleck Observatory

est. 1914

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Van Vleck Observatory
est. 1914
Middletown, CT, USA
Wesleyan University

20-inch Alvan Clark Great Refractor (0.5m, 1922)
24-inch Perkin Telescope (0.6m reflector, 1966)

Roy Kilgard (associate professor)

Website History Visiting Observing Exhibits Events

Vatican Observatory

est. 1577

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Vatican Observatory
est. 1577
Albano Laziale RM, Italy
Vatican City State

One of the oldest observatories in the world
Establishment of the Gregorian calendar
Participation in the Carte du Ciel survey

Carte du Ciel Telescope (0.33m double refractor, 1891/1942)
Schmidt telescope (0.65m, 1942)
Zeiss visual refractor telescope (0.4m, 1935)
Zeiss double astrograph (0.6m reflector/0.4m refractor, 1935)

Paul Gabor (vice director)

Website 1 Website 2 History Research Programs Visiting Tour 1 Tour 2 Media Events News Podcasts Meteor Cam

Yerkes Observatory

est. 1892

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Yerkes Observatory
est. 1892
Williams Bay, WI, USA
Yerkes Future Foundation

Largest refracting telescope in the world (1897)
First modern astrophysical observatory
Pioneer in adaptive optics

40-inch refractor (1m, 1897)
41-inch reflector (1m, 1968)
24-inch reflector (0.6m, 1964)

Amanda Bauer (deputy director)

Website History Visiting Programs Events News

Member Individuals

Visit our Observatories—Virtually

Several of our facilities have virtual tours in video or interactive form. Below are links to these media: