Jacobus ("Koos") Petterson, best known in the astronomical community for his analysis of X-ray binary systems, died at his home in Carrollton, Georgia on 30 May 1996. Petterson was born in Rotterdam, The Netherlands, on 16 August 1946 and received an MS in Engineering Mathematics in 1970 from the Technical University in Delft for work with A. J. Hermans on "a quantum mechanical treatment of the mirror electron microscope." He went on to graduate work in mathematics and physics, initially at Case Western Reserve University, and then at Yale, where he earned a PhD in physics in 1976, having investigated both general relativistic and classical effects in the vicinity of black holes and neutron stars in binary systems.
Petterson's subsequent career was tragically brief. He moved sequentially from a research associateship at Princeton (1976-77), to a visiting assistant professorship at University of Illinois (1978-80), where the students ranked him as an excellent teacher, an assistant professorship of physics at New Mexico Tech (1980-84), and the chairmanship of the physics department of West Georgia College in Carrollton (1984-88). A visiting position in astrophysics at University of California, San Diego, where he had started working on processes in elliptical galaxies like the ones he had previously studied in binary stars, was cut short by the development of the brain tumor that eventually killed him. He was a member of AAS for a relatively short period around 1980.
Koos's most-cited papers date from 1975-80 and concern streams and disks in X-ray binaries and cataclysmic variables. He was also involved in the development of half a dozen computer-graphics films illustrating Hercules X-l, SS 433, and other systems. His last paper, a collaboration with J.P. Greenberg and R. Iping on instabilities in X-ray binary disks, appeared in 1992. Petterson is survived by his wife, Rosina Iping, whom he married in 1980, and their children Ingeborg and Maximilian.
Photo (available in PDF version) courtesy Rosina Iping.