Daniel Jeremy Milton, aged 89, passed away peacefully at home, surrounded by family, in Vienna, Virginia, on May 26, 2024.
As a young geology student, Dan spent summers conducting a mineralogic study of Colorado Plateau uranium deposits, mapping in Montana, California, and New England, and planning and setting up a thermochemical laboratory. Dan obtained a bachelor’s degree from Harvard University (‘54), a master’s degree from Caltech (‘56), and a Ph.D. from Harvard (‘61), all in the field of geology, and had a distinguished 37-year career with the U.S. Geological Survey (USGS).
From 1961 to 1977, Dan was a member of USGS’ Astrogeology Branch in Menlo Park, focusing on the geology of the Moon, Mars, and terrestrial impact craters. In 1965, Dan was one of 15 candidates for NASA’s Group 4 astronaut selection process. This group, known informally as “The Scientists”, would fly on the later Apollo missions. Though ultimately not chosen, he went on to lead geological training activities and field trips to prepare astronauts for the Apollo 11 lunar landing. Dan later worked on interpreting images from the Mariner 9 mission to Mars and was one of the first scientists to credibly claim that there was or had been flowing water on Mars. He also played a role in mapping the Apollo 16 landing site in the Theophilus quadrangle.
Dan’s work on impact craters and shatter cones included fieldwork and publications related to the Campo del Cielo craters in Argentina; Henbury Crater, Gosses Bluff impact structure, Strangways crater, and Goat Paddock crater in Australia; Lonar crater in India; the Pretoria Saltpan in South Africa; the Köfels landslide in Austria; and the Qal'eh Hasan Ali maar craters in Iran.
From 1977 through his retirement in 1991, he was a member of USGS’ Eastern Environmental Geology branch, dedicating time to mapping near Charlotte, NC, Frederick, MD, the Greenbrier Fault in the Great Smoky Mountains, and Alleghanian Granite of the Central Piedmont.
Dan was a strong supporter of international cooperation in the field of geology, traveling to Kabul in the mid-1970s to train Afghan geologists and later serving as Managing Editor for the International Geology Review, responsible for identifying Russian-language articles for translation into English. Dan himself was author or co-author of more than 100 scientific or technical articles.
A frequent participant in Geological Society of Washington meetings, Dan was also a fellow with the Geological Society of America, the Mineralogical Society of America, and the Meteoritical Society (named a MetSoc Fellow in 1968), as well as an honorary fellow with the School of Earth Sciences at the Australian National University.