We are greatly saddened by the passing of our former department chair Nelson Markley on November 19, 2019, in Bethlehem, PA, at the age of 79. Nelson was a member of the Mathematics Department from 1966, when he received his PhD at Yale under advisor G. Hedlund, until 1997, when he retired from Maryland. He did research in dynamical systems, supervised 4 PhD students, and served as department chair from 1985 to 1991 and as acting vice president between 1995 and 1997. After retiring from Maryland, Nelson became Provost of Lehigh University. After retiring (again!) from that position, Nelson devoted himself to his other passion, wildlife photography, especially of birds. His website is a wonderful treasure trove of photos. He will be sorely missed by all who knew him.