by Ludwig Scheibe (TU Berlin), April 2025
In the Davis Mountains in Texas, USA, at an elevation of ca. 2000 meters, lies the McDonald Observatory, operated by the University of Texas at Austin. The dry, relatively cloud-free climate, high elevation, and the fact it is relatively far from large settlements make for good observing conditions at this location.
Photo of McDonald Observatory, with the Hobby-Eberly-Telescope on the left (Mt Fowlkes), and the Otto-Struve-Telescope and the Harlan J. Smith Telescope to the right (Mt Locke). Credit: Jason Quinn via Wikimedia Commons.
The observatory’s first director, serving from 1932 to 1947, was Otto Struve, a pioneer of exoplanet exploration. One of the telescopes at McDonald Observatory was renamed after him in 1966. Learn more about Struve’s contribution to developing the field of exoplanet research in this article about the beginnings of exoplanet exploration.
McDonald Observatory hosts a number of telescopes involved in various kinds of astronomical research, particular in the field of imaging and spectroscopy. Of particular note is the Hobby-Eberly-Telescope (HET), with its 10-m-diameter mirror one of the world’s largest optical telescopes. Installed at the HET is the Habitable-zone Planet Finder, a high-resulution spectrograph for observing exoplanets via the radial velocity method.
Among the many exoplanet-related discoveries that instruments and scientists from McDonald observatory have been involved in is the discovery of TIDYE-1b, the to-date youngest transiting exoplanet with an estimated age of just 3 million years, less than one thousandth of Earth’s age. Spectroscopic data from the Hobby-Eberly-Telescope was used to validate the gas giant and measure its mass.
Artist’s depiction of the TIDYE-1 system. While the inner protoplanetary disk – what the planets around a star form from – has been depleted by the planet itself, the outer part of the disk is probably still there at this young age. Credit: NASA/JPL-Caltech/R. Hurt, K. Miller (Caltech/IPAC)
Links for further reading:
- McDonald Observatory website by the University of Texas at Austin
- McDonald Observatory public website
- Website of the Habitable-zone Planet Finder