Mountcastle, Donald Bailey (1942—2026)

He loved the precise syncopation of a marching band, the smoky flavor of authentic Southern BBQ, the quiet wonder of the tides of Fundy Bay, and the awesomeness of a shooting star. He treasured the view from the top of a rugged hiking trail, the icy energy of a youth hockey rink, and the beauty of a piano melody echoing through his home. For Don, the world was a beautifully organized puzzle, one he could always explain with a warm smile and his favorite phrase: "It’s physics."

But more than anything, Don loved his rich life: his brilliant career, the students he inspired, and the family that loved him fiercely.

On October 2, Dr. Donald B. Mountcastle, 83, a longtime resident of Orono, Maine, passed away peacefully in Wolfeboro, New Hampshire, following a long, brave battle with Alzheimer’s.

Born in Lake Village, Arkansas, on the winter solstice, December 22, 1942, Don grew up in Columbia, Tennessee. His brilliant mind took him to Vanderbilt University, where he earned his B.S. in physics in 1964, and later to the University of Virginia for his M.S. and Ph.D. Yet, it was at UVA that Don achieved his greatest scientific discovery: his beloved future bride, Carolee Gott. Standing by the Washington, D.C. reflecting pool, he asked her to marry him, beginning a nearly six-decade love story they were married into at the UVA Chapel on August 9, 1969.

Don brought his passion for discovery to the University of Maine in 1978, spending the next 37 years as a pillar of the Department of Physics and Astronomy. He possessed a sharp, quick wit, often convincing people in an exaggerated twang that he was actually from "Southern Maine." Yet, despite a lifelong devotion to hard facts, Don maintained a deep, quiet wonder for spirituality and religion, comfortably bridging the gap between what could be calculated and what could only be felt.

He was a steady, patient, and deeply devoted father to Paul, David, Andrew, and Sarah. He was the dad who coached youth hockey teams, championed his daughter's music, led unforgettable summer camping trips, and spent countless hours tutoring his kids, and many of their friends, through high school math and science. Some of Don’s happiest memories included the family’s sabbatical in Lund, Sweden, and the epic European road trip that followed, an adventure he would always describe with a big smile as “OTROLIGT!”

In his later years, he became the proud, adoring grandfather to seven grandchildren, who brought immense joy to his life.

Don left the world a smarter, kinder place than he found it. His family takes comfort in knowing that while his physical presence is gone, his energy, as the laws of physics dictate, cannot be destroyed, it has simply changed form and remains deeply tied to all who loved him.

In honor of the rich life that Don lived, a private family service will be held at a later date. The family wishes to extend their heartfelt gratitude to Dr. Clifford Singer of Northern Light Acadia Hospital for his exceptional care and guidance. In lieu of flowers, the Mountcastle family requests that donations be made to honor Don's legacy of curiosity and care to the Alzheimer’s Association (Alzheimer's Association ) or Granite VNA of Wolfeboro (granitevna.org).