VESSOT, Robert Frederick Charles Physicist Born April 16, 1930 in Montreal, Canada, Bob was the only child of Robert Charles Ulysses Vessot, and Marguerite Yvonne (Giauque) Vessot. Bob was raised in the Town of Mount Royal, and earned a B.A., M.Sc. and Ph.D. in Physics, from McGill University in Montreal. He served in The Royal Canadian Air Force with N.A.T.O. as Station Communications Officer in Zweibrucken, Germany. In 1956 Bob settled in Cambridge, MA having been recruited by M.I.T. as a post doctorate member of the research staff working on the development of the Hydrogen Maser (Atomic Clock), invented by two Nobel Prize winners at Harvard. It was during this time that he met and married his wife of 59 years, Norma (Wight), another transplant from Montreal to the Boston area. In 1960 he moved his young family to Marblehead and went to work at Varian Associates in Beverly, MA. When Bob elected not to relocate to California upon his company’s acquisition by Hewlett-Packard, Bill Hewlett personally facilitated the move of his entire lab to the Harvard Center for Astrophysics in Cambridge, MA. He worked as a physicist at the Smithsonian Astrophysical Observatory and as an associate of the Harvard College Observatory until his official retirement in 2001, although he continued volunteering with graduate students at the lab until 2015. Over the course of his successful career, Bob was best known for his contributions to the development of the atomic clock based on the maser and its application to the experimental verification of Einstein’s General Theory of Relativity, which he performed with NASA. For this he was awarded the NASA Medal for Exceptional Scientific Achievement in 1978. The 30 atomic clocks built by his group have been used in satellite-tracking stations, in radio telescopes, in research labs in the United States and Europe, by the U.S. Naval Observatory for tracking the Nation’s time, and by Jet Propulsion Labs to guide the Voyager spacecraft to Jupiter, Saturn, and beyond. Bob received many other scientific awards, including the 1993 I.I. Rabi Award of the IEEE, authored numerous publications and owned several patents. Bob loved his work and traveled extensively throughout the world to lecture and attend conferences, often stopping in Switzerland to visit with family on his way home to Marblehead. Bob was a kind and fun-loving man who often used his many talents to help others. He enjoyed nothing more than day sailing and racing his different boats before acquiring a Nonsuch, on which he and Norma cruised for 29 years. In his beloved cellar workshop, he tinkered with motorcycles (which, in his younger years he also raced), antique cars and old marine engines. In this workshop he also produced and repaired parts for old watches and clocks, a hobby he attributed to his Swiss heritage of clock makers. Throughout his life, Bob also enjoyed tennis and skiing, listening to classical music and playing his pianos and reed organ. In his later years, he became a devoted Patriots, Bruins and Red Sox fan. Bob was an active member of the Eastern Yacht Club in Marblehead as well as many professional and social organizations. He is survived by his wife Norma Newman (Wight) Vessot and their daughters, Judy Gardiner and her husband, Joel, Peggy Lyons and her partner, Tim Moran, and Nancy Thorne and her husband, Charlie. Bob also leaves his six grandchildren, Alex and Tory Gardiner, Lindsay and Hannah Lyons, and Ben and Sam Thorne, plus many nieces and nephews and their families in the U.S., Canada and Bermuda. Bob will be greatly missed by his loving family and friends. A private service will be held this summer.