Arlo U. Landolt (1935-2022)

From his beginnings in a one-room school in rural Illinois, Arlo Landolt went on to become a renowned scientist who made fundamental contributions to science through his pioneering work in photoelectric photometry and the creation of the Landolt Standard Fields, which continue as an essential astronomical resource to this day.

Arlo’s achievements and leadership in the field of photometry and his contributions to the international professional astronomical community resulted in his earning the respect and admiration of his colleagues worldwide. However, it was his humble, friendly, and inclusive nature which broadened this respect to include appreciation, and which endeared him to them and made it a joy to know him.








It was always a pleasure to have the opportunity for conversation with Arlo. Whether encountering him at a meeting, during a visit to AAVSO HQ or other institution, while sharing a a meal or a walk, or speaking on the telephone, he was an interesting and thoughtful conversationalist and a good listener. His kindness and gentlemanly courtesy shone through and one’s day was brighter for that encounter. And, there was often a good story and a clever pun or two in that conversation, delivered with a wonderful smile and a twinkle in the eye!

Arlo was part of the AAVSO for decades. He became a member in 1997, and prior to that had been a colleague for many years, utilizing AAVSO data and resources in his research. He served four terms on the AAVSO Council/Board, gave much thought and energy to the Journal of the AAVSO and its future, and was a generous financial supporter of the AAVSO and its works.

Many tributes have been given to and about Arlo that speak of his contributions to science and his mentoring of generations of students and colleagues. The AAVSO was proud to recognize him in 2019 with a Special Citation in part for his service to the AAVSO and his work on behalf of the JAAVSO, and in 2021 with its William Tyler Olcott Distinguished Service Award. That citation summary reads: “for his promotion of variable stars and astronomy; his AAVSO membership since 1997 and over ten years of service on the AAVSO Council/Board; his pioneering work in photoelectric photometry, and the creation of the Landolt Standard star fields, which established a firm photometric foundation used by both professional and amateur astronomers; his leadership in the IAU Photometry community since 1979; and his mentoring of many AAVSO members, being always willing to listen and to offer advice.”

The full citation also includes some of the scientific highlights of Arlo’s career and a link to a fascinating interview with him.

Arlo Landolt will be remembered with great respect and appreciation by the scientific community, and also with great affection by those who were fortunate enough to know him. We extend our deepest sympathies to his beloved wife, Eunice, and their treasured families, as well as to his many students, colleagues, and friends.


               -- Elizabeth O. Waagen, AAVSO