Mark A. Gordon

Mark A. Gordon, National Radio Astronomy Observatory (NRAO) Emeritus Scientist and a pioneer of millimeter-wave astronomy, died on April 27, 2024. Mark was the Assistant Director of NRAO Tucson Operations during its most influential years and was a key contributor to the concepts for the Millimeter Array, the predecessor of the Atacama Large Millimeter / Submillimeter Array (ALMA).

Mark was born in 1937, attended Phillips Academy in Andover, Massachusetts, and was a graduate of Yale University. After wintering over in Antarctica in 1960 as part of the US Antarctic Research Project conducting auroral research, the U.S. Board of Geographic Names named Gordon Valley in the Queen Alexandra Range in his honor.

Mark received his PhD from the University of Colorado in 1966 with a thesis entitled "The Polarization and Spectral Dependence in the Fine Structure in Jupiter Radio Bursts" under the direction of James Warwick. He then spent three years on the staff at the MIT Lincoln Laboratory and studied the newly-discovered radio recombination lines in HII regions with the Haystack 37-m radio telescope.

Mark joined the National Radio Astronomy Observatory in 1969 and contributed to the development of the 140 Foot Telescope in Green Bank, WV. From 1973 to 1984, Mark was the first Assistant Director for Tucson Operations during the time that the 36 Foot Telescope pioneered the field of millimeter-wave molecular spectroscopy. Mark is credited with establishing the 36 Foot as a reliable and highly productive user facility and originated the plan for its upgrade to the 12 Meter Telescope in 1984, setting the stage for a generation of new astronomical facilities.

Mark was the project manager for the 25-meter Millimeter Wave Telescope proposed for Maunakea and was on the technical committee responsible for the design of the VLA antennas. In 1993, he became the first Division Head for Chile for the Millimeter Array (MMA), recommended that the array be sited in Chile, and developed an operations plan with estimated costs for a Chile-based facility, laying the foundation for the eventual ALMA. Mark retired from NRAO as Emeritus Scientist in 2003.

Mark was an expert in radio recombination lines, and co-author with R. L. Sorochenko of Radio Recombination Lines, their Physics and Astronomical Applications. Mark also authored the book Recollections of Tucson Operations, The Millimeter-Wave Observatory of the National Radio Astronomy Observatory, one of the most complete accounts of the early history of millimeter-wave astronomy.

He was a member of the American Astronomical Society, the International Astronomical Union, and was Chairman of Commission J (radio astronomy) of the United States section of the International Radio Science Union (URSI). He was an Adjunct Professor with the Department of Astronomy of the University of Arizona and an Adjunct Astronomer with its Steward Observatory.

Mark remained active in retirement and was a generous and prolific contributor to the NRAO Archives. The finding aid to his contributions is located at https://www.nrao.edu/archives/gordon-finding-aid.

Mark was gracious with a wry sense of humor. He had many hobbies, including sailing and bicycling, and in 1976 rode 1000 miles as part of the BikeCentennial. He will be greatly missed as a colleague, member of the NRAO staff, and pioneer of millimeter-wave astronomy.