Nadine G. Barlow died on Monday, the 17th of August, 2020.
Nadine Gail Barlow (1958−2020) has passed away after a two-year battle with metastatic ovarian cancer.
A native of San Marcos, California, Nadine became interested in astronomy during a 5th grade field trip to the Palomar College Planetarium. A year later, she received her first telescope from her father. She also gained an appreciation for geology during the annual family vacations, during which they traveled across the country by car and stopped at many of the United States national parks and monuments. Nadine studied first at Palomar Community College, transferring to the University of Arizona, where she majored in astronomy with a joint minor in geology and chemistry. She received her B.Sc. in 1980. During her last semester, she took a planetary geology class and knew that was what she wanted to study, since it combined her interests of astronomy and geology. She taught for two years at Palomar College, returning to get her Ph.D. in planetary sciences from the University of Arizona in 1987 under Robert Strom.
After receiving her Ph.D., Nadine moved to Houston, Texas, for a post-doctoral position at the Lunar and Planetary Institute followed by a National Academy of Sciences/National Research Council Assistantship at NASA’s Johnson Space Center. She also taught astronomy and planetary geology courses part-time at the University of Houston Clear Lake (UHCL), where she realized that she enjoyed both teaching and research. Nadine then spent 6 1/2 years at the University of Central Florida teaching in the Department of Physics, and restoring the university’s Robinson Observatory while serving as its director. During her last year at UCF, Nadine was honored with both the UCF College of Arts and Sciences Excellence in Undergraduate Teaching Award, 2002, and the overall university Excellence in Undergraduate Teaching Award, 2002.
Homesick for the spectacular geology and dark night-time skies of the West, Nadine became an Assistant Professor at Northern Arizona University beginning in 2002. In her 18 years at NAU, she ascended the academic ranks, eventually becoming Department Chair of Astronomy and Planetary Science. Nadine received numerous awards for teaching excellence (e.g., the NAU Research and Creative Activity Award for Most Effective Research Mentor, 2011). Largely responsible for doubling the size of the Department, she grew its curriculum into a Ph.D.-granting program. Nadine supervised many students over the years, both undergraduate and graduate, and was a popular mentor and friend to those under her tutelage. A prize for Undergraduate Research Excellence is being established at NAU’s Department of Astronomy and Planetary Sciences in her name.
Nadine specialized in impact cratering processes, particularly on the planet Mars. For her Ph.D. dissertation − almost on a dare − she mapped, measured, and classified every crater on the entire planet larger than 8 km (5 miles) in diameter, pushing the Viking imagery to its limiting global resolution. These data were used to establish the detailed relative chronology of Martian geologic features. Nadine extended this work by proposing a system of nomenclature for the craters on Mars that exhibited fluidized ejecta , a population comprising almost all Martian impact craters ranging from 1 to 100 km in diameter. This has been the bedrock interpretive study used to define the morphometry and morphology of these craters. It contributed directly to our understanding of the existence and form of water in the surface and upper layers of Mars. Nadine’s description of the crater morphology was adopted as the international standard for Martian crater morphology in 2003.
Throughout her career, she maintained and expanded this database, as later spacecraft missions returned increasingly detailed images of Mars. Nadine used the morphologies of layer ejecta to determine the depths to subsurface reservoirs of volatiles on Mars . She identified and quantified the different degradation processes affecting Martian craters. She investigated the role of the historical change of Mars’ pole obliquity on the formation and degradation of high-latitude craters in the creation of Low-Aspect-Ratio Layered Ejecta and Pedestal craters observed only at mid-to-high latitudes on Mars . She compared layered ejecta and central pit crater structure from Mars − having both an atmosphere and ground water/ice, and Ganymede − having ground ice but no atmosphere, to determine what effect an atmosphere plays in the formation of these surface layers. She authored the textbook Mars: An Introduction to its Interior, Surface, and Atmosphere in 2008 , which was updated and reissued in 2014 . Asteroid 15466 Barlow is named in her honor by the International Astronomical Union.
Nadine was central to the creation of the Mars Crater Consortium in the late 1990s. This has become the Planetary Data Consortium, comprising about 30 international impact-cratering specialists. It provides a forum for the discussion of studies of the morphology, occurrence, effects, and implications of impact craters on all planetary bodies, and is open to anyone interested in the study of impact crater morphology and morphometry and their populations on planetary bodies. Nadine served as the chair of this consortium for the first 15 years of its existence, establishing its direction and character.
The wider planetary science community also benefited from Nadine’s involvement. She served the Division for Planetary Sciences, American Astronomical Society, as Press Officer, Treasurer, and on the governing committee. She served on the Meteoritical Society’s Barringer Award Committee. Nadine brought the Arizona Space Grant Program to NAU, and fostered cooperation between NAU, Lowell Observatory, and the US Geological Survey. She served as the Director, NAU Space Grant Program and Associate Director, Arizona Space Grant Consortium.
Friends and colleagues remember Nadine’s positive outlook toward life, describing her thusly: “When I think of her, I think of her smiling and laughing.” “She was always so upbeat and uplifted those around her.” “I met her once at a conference and she was the kindest, most gracious person you'd come across in the room.”
Nadine loved her cats, Mexican cuisine, travel, baseball (especially the California Angels), anything purple, and the geology of Flagstaff. She had a special affinity for Meteor Crater, where some of her ashes were scattered. The rest of her remains are buried next to her parents in Minnesota. She is survived by her sister, Sharlyn Hayden of Reno, Nevada, several nieces and nephews and their families.
Throughout her career, Nadine made many lifelong friends, and she will be missed by all of us.