William James Roberts (1942 - 2022)

William James (Jim) Roberts died at home in Baltimore, Maryland on Sunday, January 2, 2022. He was 79.

Jim was born on April 26, 1942, in Fort Worth, Texas. He grew up in Des Moines, Iowa and Fairbanks, Alaska, graduating from Fairbanks High School in 1959. He graduated from Harvard University in 1966 with an A.B. in Chemistry and Physics. He completed his graduate work in Astronomy at the University of Washington and at Caltech. He received his Ph.D. from the University of Washington in 1976 with a dissertation on "Electrodynamics of Neutron Stars" advised by George Wallerstein. Jim then accepted positions as Visiting Associate at Caltech where his mentor was Peter Goldreich, a Staff Scientist at Applied Theory, in Los Angeles, and a Research Scientist at the Planetary Science Institute (PSI), Pasadena from 1974-1979. At PSI, Jim co-authored a number of papers on Martian erosive flows and other features imaged by NASA’s Viking 1 orbiter.

Jim's initial research was on pulsars, but his interests and contributions varied widely. He contributed to the understanding of the bizarre behavior of the X-ray pulsar, Hercules X-1. This work was published in the much-cited Astrophysical Journal paper "A slaved disk model for Hercules X-1," in 1974. He also pursued problems in the Cepheid-based distance scale of the universe, in the corotation of neutron star atmospheres, and contributed to the model for the object SS433.

Jim took a hiatus from astronomy and ran a small computer consulting business in Los Angeles in the 1980s. Relocating to Baltimore, Maryland in 1988, he returned to astronomy as an Operations Astronomer for the Computer Sciences Corporation at the Space Telescope Science Institute, where he worked until 1994. Although the job required no research, Jim actively pursued research opportunities, co-authoring a number of papers with European astronomers on stellar populations and abundances in the Sculptor and Fornax dwarf galaxies and the Magellanic Clouds, and with D. Jack MacConnell on proper motion measurements from the Palomar Schmidt survey plates.

Jim was an outdoor enthusiast and enjoyed spending time in the mountains and desert. He was active in the Angeles Chapter of the Sierra Club in Los Angeles from 1981 to 1988. He was an Assistant Leader of the Basic Mountaineering Training Course and led several peak climbing trips for the Sierra and Desert Peaks Sections. Always on the lookout for thrills, he sought out the fastest, highest, and meanest roller coasters in the land.

Jim is survived by his wife of 39 years, Doris McClure; and children from a previous marriage: son Monty Hitschler (Jodi); daughter Sarah Wyeth (David); brothers David Roberts (Nancy) and Thomas Roberts (Laura); and three grandchildren, Chloe Hitschler, Phoebe Wyeth, and George Wyeth.