• 1926

    W.J. McDonald Bequest

    Paris, Texas banker William Johnson McDonald left the bulk of his fortune to The University of Texas at Austin “for the purpose of aiding in erecting and equipping an Astronomical Observatory to be kept and used in connection with and as part of the University for the study and promotion of the study of Astronomical Science.”

  • Otto Struve

    November 1, 1932

    Otto Struve Directorship

    Astronomer Otto Struve was the first director of McDonald Observatory. He served from November 1932 to August 1947, and was concurrently director of The University of Chicago's Yerkes Observatory.

  • Yerkes Obs.

    November 23, 1932

    University of Texas Partners with University of Chicago

    When The University of Texas at Austin received W.J. McDonald's bequest for building an observatory, it had no astronomy department. The University of Texas entered into an a agreement with the University of Chicago, which had many fine astronomers and its own Yerkes Observatory. The deal allowed for the University of Chicago to operate McDonald Observatory for 30 years.

  • The two large domes in the foreground house the 2.1-meter (82-inch) Otto Struve

    April 17, 1933

    Donation of Mount Locke

    Mrs. Violet Locke McIvor donated the mountain upon which now sit most of McDonald Observatory's telescopes. Previously called "Flat Top" or "U Up and Down Mountain" (for the ranch in which it sat), it was renamed Mount Locke in honor of Mrs. McIvor's grandfather. Dr. G.S. Locke of Concord, New Hampshire, was the founder of the ranch.

  • HET

    August 3, 1933

    Donation of Mount Fowlkes

    After receiving the donation of Mount Locke (previously called Flat Top) as the site for the new observatory, planners thought they should acquire the nearby smaller mountain (Little Flat Top) for possible future expansion. They received the donation from the estate of Fort Davis Judge Edwin H. Fowlkes, for whom the mountain was re-named. Decades later, the Hobby-Eberly Telescope (one of the world's largest optical telescopes) was built atop Mount Fowlkes.

  • May 5, 1939

    Dedication of McDonald Observatory

  • Titan


    Discovery of Titan's Atmosphere

    Gerard Kuiper discovered the atmosphere of Saturn’s moon Titan, the first detection of an atmosphere for any moon in the solar system.

  • September 1, 1947

    Gerard Kuiper Directorship

    Astronomer Gerard Kuiper served as director of McDonald Observatory for approximately two years.

  • 1951

    Bengt Strömgren Directorship

    Bengt Strömgren served as director of McDonald Observatory from January 1951 through August 1957.

  • 1955

    Improving the View

    Harold Johnson and W.W. Morgan devised a system for measuring the colors of stars. The system, which is still in use today, allows astronomers to remove the effect of interstellar dust, which makes stars look redder.

  • September 1, 1957

    Second Kuiper Directorship

    Gerard Kuiper served a second time as director of McDonald Observatory from September 1957 to March 1959.

  • April 1, 1959

    William W. Morgan Directorship

    William W. Morgan served as director of McDonald Observatory from April 1959 to August 1963. He was the final McDonald director from the University of Chicago.

  • 1963

    Shape of the Milky Way

    Gerard De Vaucouleurs proposed that the Milky Way galaxy is a barred spiral, with spiral arms extending from a long “bar” of stars in its center.

  • September 1, 1963

    Harlan J. Smith Directorship

    Harlan J. Smith was the first University of Texas director of McDonald Observatory, and served simultaneously as chair of the new astronomy department in Austin. Among many other accomplishments, he led the construction on the 107-inch telescope that now bears his name. More information on Harlan J. Smith is available on his University of Texas memorial page.

  • The 2.7-meter (107-inch) Harlan J. Smith Telescope at the University of Texas Mc


    Dedication of the 107-inch Telescope

    Dedication of the 107-inch (2.7-meter) Telescope. It was later renamed the Harlan J. Smith Telescope in honor of the observtory director responsible for its construction.

  • The 2.7-meter (107-inch) Harlan J. Smith Telescope at the University of Texas Mc


    Coude Spectrograph

  • 1969

    Bouncing a Laser Off the Moon

    One month after Neil Armstrong took the first “small step” on the Moon, McDonald Observatory bounced a laser beam off a reflector left on the Moon by Apollo 11. The experiment measured the Earth-Moon distance with an accuracy of a few inches.

  • 1970

    Invention of High Speed Photometry

    An instrument developed by R. Edward Nather opened a new field of astronomy, high-speed photometry. It allows astronomers to measure changes in an object’s brightness on timescales of a thousandth of a second or less. Among other things, it has been used used to discover rapid pulsations in white dwarfs, the “corpses” of once-normal stars like the Sun.

  • 1976

    Sizing Up the Stars

    Tom Barnes and David Evans published a method for determining a star’s size by measuring its brightness and temperature. Known as the “surface brightness relation,” it is still a commonly used technique today.

  • StarDate logo

    October 1, 1978

    StarDate Radio Program Debuts

    McDonald Obervatory's StarDate radio program debuted on the nation's airwaves, initially funded by a grant from the National Science Foundation. Today, StarDate is the longest running, nationally syndicated science show on radio. It currently airs on more than 300 stations. More information is available at StarDate Online.

  • 1982

    W.L. Moody Visitors Information Center opened

    The W.L. Moody Visitors Information Center opened in 1982. For two decades, it served thousands of visitors to McDonald Observatory.

  • 1991

    Frank N. Bash Directorship

    Astronomer Frank N. Bash served as director of McDonald Observatory from 1991 to 2003, and served two years as interim director from 1989-1990.

  • Hubble Space Telescope


    Helping with Hubble Space Telescope

    NASA launches Hubble Space Telescope, which was developed and planned with the input of several University of Texas astronomers and engineers. In particular, Fritz Benedict and Bill Jeffreys led a team developing the telescope's Fine Guidance Sensors, which allow it to point precisely at cosmic targets. Today, McDonald astronomers routinely use Hubble and other space-based telescopes in their research.

  • The primary mirror of the Hobby-Eberly Telescope (HET) at McDonald Observatory.


    Dedication of Hobby-Eberly Telescope

    The innovative Hobby-Eberly Telescope was dedicated. It uses a mosaic of 91 individual mirror segments to create a primary mirror with an effective light-gathering power of a single 9.2-meter mirror.

  • 2002

    First Planet Orbiting a Close Binary Star

    Using the Hobby-Eberly Telescope, McDonald astronomers including Bill Cochran discovered the first planet orbiting a close-together binary star system. It is one of many exoplanet discoveries made at McDonald.

  • April 6, 2002

    Frank N. Bash Visitors Center opens

    The 12,000-square-foot Frank N. Bash Visitors Center opened. Originally called the Texas Astronomy Education Center, it features an interactive exhibit, 90-seat theater, cafe, gift shop, and outdoor telescope park and amphitheater. It was later renamed the Frank N. Bash Visitors Center for the the former director of McDonald Observatory.

  • 2003

    David Lambert Directorship

    Dr. David L. Lambert became director of McDonald Observatory in 2003. Lambert also holds the Isabel McCutcheon Harte Centennial Chair in Astronomy, and has been a professor at The University of Texas at Austin since 1969. He retired as observatory director in 2014.

  • 2005

    Most Powerful Supernova

    An automated search using a McDonald telescope discovered the most powerful supernova to date, Supernove 2005ap.The exploding star briefly shone 100 billion times brighter than the Sun. The Texas Supernova Search project was run by University of Texas graduate student Robert Quimby using the ROTSE IIIb telescope at McDonald.

  • 2007

    Dark Energy Search

    McDonald astronomers Gary Hill and Karl Gebhardt began developing the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). It will examine more than one million galaxies to probe the nature of dark energy, which is causing the universe to expand faster as it ages.

  • Taft Armandroff with Struve Telescope dome

    June 1, 2014

    Taft Armandroff Directorship

    Taft Armandroff became director of McDonald Observatory on June 1, 2014. He had previously served as director of the W.M. Keck Observatory in Hawaii. Armandroff's research specialties include dwarf spheroidal galaxies, stellar populations, and globular clusters.

  • June 3, 2015

    Construction Begins on Giant Magellan Telescope

    Eleven international partners, including The Univesity of Texas at Austin, announced June 3, 2015, that they had approved the start of construction on the Giant Magellan Telecope (GMT). The telescope is poised to become the world's largest. It is expected to see first light in 2021 and be fully operational by 2024.