About McDonald Observatory

McDonald Observatory, a research unit of The University of Texas at Austin, is one of the world's leading centers for astronomical research, teaching, and public education and outreach. Observatory facilities are located atop Mount Locke and Mount Fowlkes in the Davis Mountains of West Texas, which offer some of the darkest night skies in the continental United States. Additionally, the observatory is a partner in the forthcoming Giant Magellan Telescope, under construction in Chile. McDonald Observatory's administrative offices are on the UT Austin campus. The Observatory works with the University's Department of Astronomy on both research and teaching. McDonald's principal research telescopes include:

The Giant Magellan Telescope

The Giant Magellan Telescope (GMT) now under construction in Chile is the first in a new generaion of extremely large telescopes. Its seven mirrors will span 25 meters. UT Austin is a founding partner in the collaboration which includes several other U.S. universities and partner institions from around the world. The telescope is expected to see first light in 2021 and be fully operational by 2024. More information is available at the project website.

The Hobby-Eberly Telescope

With its 10-meter mirror, the HET is one of the world's largest optical telescopes. Completed in 1997, the telescope has recently undergone a complete upgrade. The HET is optimized for spectroscopy, the decoding of light from stars and galaxies to study their properties. This makes it ideal for searching for planets around other stars, as well as probing distant galaxies, exploding stars, black holes, and more. Soon, the telescope will begin a major study of dark energy, the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). The HET is a joint project of The University of Texas at Austin, The Pennsylvania State University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.

The Harlan J. Smith Telescope

Constructed 1966-68, the Smith Telescope has a 2.7-meter (107-inch) mirror, which was the third largest in the world when built. The telescope is used every clear night of the year.

The Otto Struve Telescope

Constructed 1933-39, the Struve Telescope was the first major telescope to be built at McDonald Observatory. Its 2.1-meter (82-inch) mirror was the second largest in the world at the time. The telescope is still in use today.

Other Telescopes

McDonald also operates several one-meter class telescopes. These include MONET/North, a node of the Las Cumbres Observatory Global Telescope Network, as well as 0.9-meter (36-inch) and 0.8-meter (30-inch) telescopes. Additionally, the Observatory is home to the 0.8-meter (30-inch) McDonald Laser Ranging Station operated by UT Austin's Center for Space Research, a 20-inch telescope operated by Boston University, and a 0.45-meter automated telescope that is part of the ROTSE collaboration.

Public Education and Outreach

McDonald Observatory operates a multi-faceted international public outreach program. At the on-site Frank N. Bash Visitors Center, outreach events include star parties, public tours, K-12 teacher and student activities, and more. McDonald also produces the StarDate radio program, StarDate magazine, the StarDate Online website, and special programs for hundreds of elementary and secondary teachers across the United States.

domes with star trails

Mt. Locke Domes with Star Trails

Present & Past

Want to find an astronomer, staffer, or student at the Observatory or in the UT Austin Astronomy Program? Check the Astronomy Program Directory.

Learn more about the history of the Observatory through our interactive timeline, and suggest milestones to add to it.

Memories Blog
Have a favorite memory of McDonald Observatory? Share your stories and photos of the Observatory on our interactive blog, and read others' stories from the 1930s right up until today.