Frederic John Eppling, age 95, died peacefully on July 16, 2015 of congestive heart failure at Emerson Hospital in Concord, MA. His loving family and friends surrounded him. At the time of his passing, Frederic was a physicist at MIT's Laboratory for Nuclear Science, and was a resident of Lincoln, MA, where he lived for 59 years. Frederic was born in Sheboygan, Wisconsin on March 16, 1920. He was awarded B.S. (Phi Beta Kappa, Magna Cum Laude), M.S., and Ph.D. degrees in physics from the University of Wisconsin. He distinguished himself academically by designing and building a mass spectrometer or atom sorter. Frederic made significant contributions to particle, high-energy, and cosmic ray physics at MIT's Laboratory for Nuclear Science. He worked there for more than 60 years, first as Associate Director of the Laboratory, and later as head of the AMS Administration and Communications Group, and Staff Physicist in the Electromagnetic Interactions Group. Among the groundbreaking research projects that Frederic helped bring to fruition were the L3 Detector at CERN (the European Laboratory for Particle Physics) in Geneva, Switzerland, and the Alpha Magnetic Spectrometer Experiment, which was deployed on the International Space Station. During World War II, Frederic was assigned to Harvard University's secret Radio Research Laboratory, and helped to devise countermeasures against enemy radar. He also served with the U.S. Navy aboard the flagship USS Estes as lead radar officer during the battles of Iwo Jima and Okinawa. After 30 years, he retired as Captain from active Naval Reserve duty. Frederic's unflagging devotion to his family and profession, and fierce desire to remain active and independent until his final days, were an inspiration to all who knew him. Many will also remember him fondly as an ardent fan of the New England Patriots and Green Bay Packers football teams. His cherished wife Sarah "Sally" Hennessey, whom he married in 1947 in Marblehead, MA, predeceased Frederic in 1997. His four devoted children, John Eppling of Lincoln, MA, Ann Eppling of Concord, MA, Patricia Prior of Tiverton, RI, and Michael Eppling, and his wife Susan, of Lexington, MA, survive him. His loving grandchildren Emalie Prior of Somerville, MA, and Brendan Prior of Bristol, RI also survive him. Visiting hours will be held on Tuesday, July 21st from the Dee Funeral Home, 27 Bedford Street, CONCORD CENTER from 4 to 8 PM. Funeral from the Dee Funeral Home will be held on Wednesday, July 22nd at 9 am followed by a procession to Lincoln Cemetery, Lexington Road, Lincoln, where a graveside service will be held at 10 am. Officers of the U. S. Navy will present military honors at the cemetery.