Jeannene Mattingly Hanson

Jeannene Mattingly Hanson, 89, of Los Alamos, New Mexico, passed away on November 16, 2025. She was born on January 9, 1936 in a farmhouse near Portland, Kansas to Ruther Meder Mattingly and Ena Mae Lott Mattingly. After graduating from high school in Caldwell, Kansas, she dropped her given first name, Treva, in favor of her middle name, Jeannene, and began taking classes at the University of Kansas.

Jeannene married Robert H. Masterson in 1956 and accompanied him to Munich for his Fulbright scholarship. She later became the devoted mother of their son Robert Charles Masterson. The family lived in several states, from Richland Washington to Bellport, Long Island, NY to Evergreen, Colorado following Bob's career, eventually ending up in Los Alamos. Jeannene and Bob were divorced in 1979. Jeannene married Kenneth Hanson in 1996 and together they remained in Los Alamos the rest of her life.

Jeannene had a varied and fulfilling career. She was a self-established travel agent in Evergreen, Colorado, known for her expertise in arranging wonderful trips for her clients. Around 1976 she joined the Los Alamos National Laboratory, where she engaged in research in epidemiology; she traveled around the country collecting health data on former radiation workers, often interviewing them. Later, she worked as the group administrator of one of the largest groups in the Lab, seeing to the administrative needs of group members. Jeannene had a knack for dealing with Lab bureaucracy and she made sure everyone was given the best chance to succeed.

Jeannene loved to travel. Besides living in several states in the US, she visited many more, including two trips to the majestic state of Alaska. She visited numerous European countries, including Germany, England, Ireland, France, Austria, the Czech Republic, Italy and the Netherlands. She was captivated by the fascinating wildlife of South Africa and the Galapagos Islands. She enjoyed visiting the picturesque area of Kyoto Japan.

Jeannene had a warm and generous disposition. She routinely went out of her way to make sure people were comfortably settled. As an example, when the French graduate student Xavier Battle came to work for a year with Ken on the Bayes Inference Engine, Jeannene made a special effort to see he and his girlfriend, Anne, had what they needed to settle down comfortably in Los Alamos. Years later, Xavier's mom said she was initially concerned about Xavier and Anne coming here for a year but relaxed when she heard Jeannene had taken them under her wing.

Jeannene is survived by her husband Kenneth Merrill Hanson and her much-loved son Robert Charles Masterson and his wife Anna Patalano. She also leaves behind sister Barbara Jo Meyer and her husband Mike Meyer; step-sister Betty Frazier; grandsons Matthew, Daniel and Andrew Kempers, whom she spoiled endlessly; and her best friend Tess Gorman and her husband Tom Gorman.

Jeannene was preceded in death by her father Ruther Meder Mattingly and mother Ena Mae Lott, as well as brother Charles Edward Mattingly and sisters Bonnie Lou Smock and Julia Karel Byers.

Jeannene will be remembered for her warm and generous personality, bright and genuine smile, innate intelligence and her enduring spirit. Her legacy lives on in the hearts of those who knew and loved her.

Photos of some of Jeannene's happiest moments can be seen at https://photos.app.goo.gl/S69ihshW717LbUiN6