Nolan Walborn: A Tribute

STScI astronomer Dr. Nolan Walborn passed away on the morning of February 22, 2018. The astronomy community lost an internationally recognized scientific leader and an inspirational colleague.

Nolan pioneered the field of stellar spectroscopy of massive stars with several major discoveries. His passion for studying the brightest nearby stars in the universe, combined with his passion for sharing scientific knowledge with peers, had a major impact on the astronomical community over several decades.

During his long tenure at STScI, Walborn exemplified the Institute’s core values in his commitment to the Hubble user community through his dedicated support for complex proposal implementation strategies.

Nolan was present at the founding of the Institute in the early 1980s, and helped draft the AURA/JHU proposal to NASA to manage STScI.  In recalling the preparation of the AURA proposal, Nolan wrote, “After AURA won the competition I heard that one of the winning points of the AURA proposal was the Science Management section, which gave me a warm feeling.”

After Hubble’s 1990 launch, Nolan was personally responsible for enabling several spectroscopic programs with Hubble’s instruments that would have otherwise not been deemed schedulable. He established a long-standing legacy for all Hubble spectrographs and was instrumental in the Institute’s involvement in promoting the James Webb Space Telescope.

“Nolan unfailingly had the best interests of both the science and the workings of Hubble at heart,” said John Debes, STIS team lead. “As a manager, I often observed him being supportive of all my team members, from the newest hire to the more senior staff. I think he certainly took our spirit of equity to heart.”

Author on 214 refereed publications, Nolan was best known for his comprehensive work on the 30 Doradus region in the Large Magellanic Cloud, as well as Eta Carinae, and Theta-1 Orionis C. In the late 1980s he worked with STScI astronomer Barry Lasker in identifying the progenitor star to Supernova 1987a, which, surprisingly, turned out to be a blue supergiant star instead of the predicted red supergiant. This ultimately influenced theories of supernova evolution.

“Nolan was a towering figure in the community of researchers devoted to studying early-type stars. His familiarity with the literature and encyclopedic powers of recall were legendary,” said Alex Fullerton, instrument team lead. “He particularly cultivated personal connections with the astronomical community in South America, which includes some of his closest collaborators, and he was especially committed to seeing astronomy flourish there.”

Linda Smith, head of the Instruments Division, said that Walborn was very keen on having fun as well as interacting scientifically at astronomical conferences. “His biggest joy at conferences, however, was to dance the Macarena,” she said. “He also taught the dance to many conference attendees over the years.”

Larry Marschall of Gettysburg College, who was a fellow graduate classmate of Walborn’s at the University of Chicago in the late 1960s, remembers him as a clear, logical thinker who wasn't hesitant to offer a fresh, and sometimes contrarian, view on the issues.  “We’d discussed these topics informally at the Yerkes Observatory or at Friday fish-fries in the local restaurants.”

In the early 1970s Walborn went to Cerro Tololo Inter-American Observatory in Chile, where his research led to his recognition of the hottest class of star (O3) in the universe.  “I first met Nolan at Cerro Tololo when we were both recent Ph.D.’s.,” said Roberta Humphreys, Professor Emeritus at the University of Minnesota.  “Eventually, we became collaborators when Nolan joined our Hubble Treasury Program on Eta Carinae. He could be both insightful and critical, but with a twinkle in his eye and a sly grin afterwards.”

Reflecting the acknowledgments of many of Nolan’s science colleagues, Fullerton said, “Nolan enthusiastically shared his expertise with anyone who asked, and was passionate about transferring his deep understanding of the philosophical underpinnings of spectral classification to the next generation of researchers.” 

All of his colleagues agree that Nolan Walborn’s career was brilliant, far reaching, and consequential -- in other words, stellar.