Logan Keith Kuiper

Dr. Logan Keith Kuiper, 85, passed away in Los Alamos, New Mexico, on January 20, 2026. Born on September 12th 1940 in Oskaloosa, Iowa, to Andrew and Bess Kuiper, Logan’s journey took him from a small family farm to the forefront of physics and mathematics.

Logan grew up outside Pella, Iowa, attending the one-room Liberty Corner grade school before graduating from Pella High School. His passion for learning led him to the University of Iowa for an undergraduate degree in Mathematics. He furthered his studies at Cal Tech, earning an MS in Applied Mechanics, before returning to the University of Iowa to complete both an MS and a PhD in Physics.

His professional life was marked by a commitment to education, physics and mathematics. Early in his career, Logan joined the US Geological Survey as a Research Hydrologist. His work with the USGS took him to Iowa, South Dakota, Texas and finally Los Alamos, NM. He joined Los Alamos National Laboratory (LANL) where he applied his expertise in groundwater porous media flow research.

While living in Iowa City, Logan married Ann Gross of Cascade, Iowa. Together they raised three children—Adam, Timothy, and Siri—as his career moved the family across the Midwest and Southwest. Logan retired from LANL in 1998, choosing to spend his later years in Central America and his beloved Jemez Mountains.

In retirement, Logan frequently traveled to Central America including Belize and Costa Rica. He shared his knowledge abroad, teaching at Galen University in San Ignacio, Belize until 2016. Upon returning to New Mexico, he settled into his property in the Jemez Mountains on Cochiti Mesa. Logan became a fixture in the community of Jemez Springs, where he was a frequent visitor at Los Ojos Bar and Grill, enjoying the company of friends and neighbors.

Logan was a man of many passions: family, physics, mathematics, land investments, and global adventures. He found peace in the country and spent much of his time hiking the rugged terrain of the Jemez Mountains surrounding his home.

He is survived by his son, Adam; his son, Tim, granddaughters, Ariella and Lacey; and his daughter, Siri (Hoehn), son-in-law, Chris and grandchildren Hailey, Ryan and Jason. He was preceded in death by his parents and his sister, Darlene Picard (Roger). Logan will be remembered for his sharp intellect, his adventurous spirit, and his love for family and science.

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