> While 69 is fairly young, his death does not appear to be tragic in the sense of unfulfilled ambitions. My comment was from the perspective of course of life

> While 69 is fairly young, his death does not appear to be tragic in the sense of unfulfilled ambitions. My comment was from the perspective of course of life. After retirement, he had only 5 years to pursue "his passions of outdoor photography and protecting the environment". (Note that he did not continue working on his research.) He was under pressure to deliver results (school, working, etc.) for the majority of his life, and he had only 5 years of total and independent (within financial constraints) freedom. That is sad.