John Birmingham Corcoran was a true “maker,” someone who relished exploring the world through experimenting and building. He built with hands, his mind and his heart. A long-time resident of Newtown, he passed away in Concord, Mass., on June 29.

Jack, as most people called him, was born in New London, Conn., on October 15, 1927, the oldest of two boys in an Irish Catholic family. He was especially close with his mother, Catherine: She had been the oldest of nine children, and passed along to him her steadfast commitment to shepherding the family. Unusually for the times, Catherine had worked as a company manager until she married at age 35. His father, John E. Corcoran, loved to write but wound up working as a chemist in the Electric Boat Company in New London, which built submarines. That combination of writing and science would be vivid threads running through Jack’s life.

He enlisted in the Army at age 19, receiving an honorable discharge in Alaska, where he lingered for a few months, panning for gold. (He found a few flakes, which he kept in a bottle in his desk drawer for years.) He returned to Connecticut, earning a bachelor’s degree from Wesleyan University on the GI Bill and soon embarked on one of the great adventures of his life: Joining childhood friend, Wayne Crawford, in Japan.

Jack adored living in Yokohama and embraced Japanese culture. He built a collection of Japanese records, silk-thread artwork and a lifelong fondness for katanas and yukatas. Later, he taught his children to use chopsticks at an early age.. Well into his 90s, Jack still kept one of his Japanese business cards tucked in his wallet.

He returned to the US, settling in Chicago where he had a beloved circle of cousins. Jack wound up working as a technician at Argonne National Laboratory, the first national laboratory created in the US, which focused on peaceful uses of nuclear power. There, he encountered what would lead him on a second great exploration: computation science. In the late 1950s and early 1960s, Argonne was at the forefront of high speed computation and heterogeneous architectures, via machines named “George,” “GUS,” and “Chloe” – enormous devices that filled rooms with reels of magnetic tape and streams of punch paper tape. Jack worked in the radiological physics division, pushing forward the boundaries of computational science.

His whimsical philosophy comes through in his written reports: “The ostensible reason for writing up a program with detailed charts and diagrams of the coding is to allow ‘somebody else’ to be able to read your program. On several occasions I have been that ‘somebody else’ to a program and the experience has made me a true believer in the school of opinion that says ‘better to write your own from scratch than try to absorb someone else's.'"

Jack also started a family in Chicago: Like his mother (and with a helpful nudge) he married in his mid 30s, after courting fellow Connecticut native, Virginia Dombe.

With two young children in tow, Jack and Virginia returned to Connecticut, eventually settling in Newtown, Conn. The work Jack had done at Argonne set him up for his next adventure, joining an electronic instrument company called Perkin Elmer. There, he rode the cutting edge of technology for the next thirty-plus years of his career.

Over the years, Jack built many things: He taught his children to construct Estes model rockets and Heathkit electronics. He raised bonsai trees and built a tiered shelf to display them. He dug a deep trench alongside the driveway, layering it with gravel and sifted soil so he could raise exquisite roses. He spent weeks gradually adding weights on either end of wooden beams to curve them to build a gently arching bridge over a small stream adjacent to the family home. And when he encountered a large rock in the backyard where he wanted to build a porch, he convened a “braintrust” of local high school students to consider how to get rid of the rock (blow it up? erode it with acid?) before conscripting them in the backbreaking exercise of digging it up. Friday evenings were precious family time, featuring martinis (for the adults) and cheese and crackers for all, accompanied by the sweet sounds of his Japanese records, interspersed with Herb Alpert and the Tijuana Brass, Miles Davis, Dave Brubach and Chet Baker. Although he ruefully recalled how elementary school teachers dismissed him from the school choir, Jack whistled melodically and loved music.

For decades, he could not talk about his work at Perkin Elmer, which happened in rooms without windows. Eventually the work was declassified: it turned out he had a pivotal role in writing the software used by the spy satellites that surveyed the Soviet Union throughout the Cold War. He also helped write the fine-guidance software for the Hubble Space telescope. He was a fan of alternative computer architectures, nudging PE to invest in massively parallel computing (i.e. Danny Hillis’ “Thinking Machine,” in the 1980s) and writing a detailed plan for how PE could lead in artificial intelligence in 1984. (The company ultimately did not.)

He mentored other engineers and was particularly proud of women engineers who flourished under his guidance. He encouraged his wife, Virginia, who worked as a librarian and office manager for decades. He even argued with Virginia over whether their daughter should take a typing class in high school. (“She’ll get stereotyped,” he protested.) Happily, he lost that debate.

In retirement, Jack turned to film making, delighting in making video productions of friends and family, including his grandchildren and fellow retirees at Southbury’s Heritage Village. He wrote essays on computers under the pen name of “Virtual Jack,” and experimented with writing short plays.

With Virginia’s encouragement, he took an active part in volunteering for local libraries, helping organize Newtown’s famous annual book fair. Together, Jack and Virginia also traveled to California, Hawaii, Ireland and across Canada by train. Throughout all his adventures, Jack maintained his optimism in the future, and his belief that we could build amazing tools to make the world a better place. In his 90s, he listened with rapt attention to descriptions of the advances in generative AI technology. “Oh,” he said with a touch of wistfulness, “it would be great to be part of that.”

Jack passed away in Massachusetts on June 29, 2025, under the care of his son, Christopher, and daughter, Betsy. He was preceded by Virginia, his wife of 63 years, who passed on March 28, and his brother, Gerald Corcoran. He will be deeply missed by his family including Chris and Katya (Concord, Mass.), and Betsy and George Anders (Burlingame, Calif.); his grandchildren, Peter and Emily; and a wide circle of nieces, nephews and friends. Jack and Virginia will be laid to rest in Newtown in October. In lieu of flowers, well-wishers are encouraged to donate to the Massachusetts Audubon Society in Jack and Virginia’s honor.