James Robert Jensen

James Robert “Bob” Jensen, of Columbia, Maryland, passed away unexpectedly at home on April 29, 2025.

Bob was born in Milwaukee, Wisconsin on September 21, 1951, to Vernon Allen Jensen and Gwyneth Love Jensen, and grew up in Arlington Heights, Illinois. He earned his BA in chemistry from Cornell College in 1973, followed by a PhD in physical chemistry from the University of Wisconsin-Madison. It was at the university where he met Deborah May Landmark, whom he married on September 23, 1978. The couple moved to Maryland shortly after, where Bob began a 46-year career at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland.

Throughout his career, Bob was a vital team member on many significant space exploration projects. His expertise in radar technology and passionate curiosity made him a valuable contributor to missions including TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics Mission), NEAR Shoemaker (the first spacecraft to orbit and land on an asteroid), MESSENGER, STEREO, CONTOUR, Deep Space Network, Deep Space Advanced Radar Capability (DARC), and Mini RF.

His team at APL remember him as a talented engineer and vibrant member of the team. Colleagues recall that it was always a pleasure to walk into his office with a question, and that he was generous with his time and talents. Later in his career, he spent time tutoring junior staff and passing down his knowledge and expertise.

Although he officially retired in 2020, Bob's passion for his work led him to continue his involvement with several projects, including the New Horizons spacecraft with which he was involved since its inception. His nearly 20 years of critical contributions to this project included enabling navigation and communication with the spacecraft whose primary mission was a flyby study of the Pluto system in 2015. In 2025, a minor planet* in our solar system was named after him as a result.

Following his retirement, he and Deborah traveled extensively with their friends Sue and Bill, Bob’s friend of more than 50 years. Together they traveled around the country and abroad, recently fulfilling Bob’s dream to take a cross-country rail journey which took them through the Rocky Mountains in Canada.

His hobbies and interests were wide-ranging, including 3d printing, coding, and programming electronics, poker nights with a long-standing group of friends, listening to old time radio programs, and collecting “Pogo” comics.

He was a loving husband, father, and grandfather, a steady presence always willing to listen and teach. He enjoyed spending time with his grandchildren, sharing with them the joy of curiosity,
experimentation, and problem-solving.

He is survived by his wife, Deborah; three daughters, Laura Jensen (and husband Matt Walley), Christine Bryan (and husband Don), and Beverly; his siblings, Lynn Huffman, Jeff Jensen, and Julie Savage; and three grandchildren, Caleb, Greta, and Amelia.

He will be greatly missed.

In lieu of flowers, donations may be made in Bob’s memory to ABN Old-Time Radio or to the B&O Railroad Museum.

*228409 Bobjensen - Discovered 2001-Mar-26 by Buie, M. W. at Kitt Peak, near Tucson,
Arizona.