Daniel M. Sunday, Jr.

Daniel M. Sunday, PhD died peacefully in his sleep on Friday May 6, 2022, in hospital while being tested for cancer. He was born in Queen's, NY on August 30, 1944, first son of Mary Lucille (née Durber), and Daniel Mullane Sunday, Sr. His brothers were born in DC, NJ, and NY, then all moved to Canada in 1953, where his sister was born. Dan graduated from University of Toronto with his honours BSc in mathematics, then did his PhD in Algebraic Topology at University of Minnesota. He became an expert in Differential Geometry and Computer Graphics, working as a mathematician at Universidad de Los Andes, Mérida, Venezuela, and at UC Berkeley. In 1982, he began work as a mathematician and Research Director at Johns Hopkins Applied Physics Lab (APL), until retiring after 32 years. He recently wrote 2 popular books: Greek Geometry: Secrets of the Ancient Mystics Revealed (2020), and Practical Geometry Algorithms with C++ Code (2021).

Dan is survived by Jassica, the love of his life; they married in 1983 and lived in Maryland. He is also survived by his siblings, many nieces and nephew, and extended family: Bob (Ottawa): former spouse, Jane Sullivan, children Julie [Mark McLaughlin; formerly Michael Iles, children: Ella, Charlotte, and Madeleine], and David [Katherine, children Iain and Maeve]; Joe (Toronto): Suzanne, children Suchot [Simon Statkewich, Olena] and Courtney [Michael Jurkiewicz, Theodore and Oliver]; Eugene (New Brunswick, Canada): Kathy White; child Waverley Birch; and Mary Sunday (Durham, NC): Chris Willett, children Elizabeth (Dan's godchild), Julian Daniel Sunday Willett, and Ashlan.

As Research Director at APL, Dan enjoyed the top-secret work. He often directed "War Games" to check computer systems on aircraft carriers, including during the Gulf War. As a civilian, they housed him in captains' quarters, which was exciting, as he slept under the jet landing pad. Dan said his greatest achievement at APL was developing a program to quickly locate and save pilots who crash into the sea in only 30 seconds. Previously, it took over 30 minutes, with dire results.

Dan loved playing golf and chess with Jassica, wildlife photography, gardening, watching late-night movies, and visiting family in Korea, Canada, and the US. His life was driven by a deep desire to do good, through both his work and family. He was a perfectionist and yet uniquely vulnerable to his own humanity. He was a survivor, using creative humor to cope with life's struggles. He was extremely dedicated to those he loved, especially Jassica, his siblings and friends, incapable of lying or deception, and honest about his opinions. He is sorely missed.

Family and friends are welcome to services for Dan on Tuesday, May 17 at the Harry Witzke Funeral Home in Ellicott City, MD: Visitation from 11-12 noon; funeral service in the Chapel at 12 noon, followed by private burial at St. Louis Cemetery. In Dan's memory, donations could be made in his name to St. Louis Roman Catholic Church, Clarksville MD, the Smithsonian, or World Wildlife Fund.

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