Bill's smile lit up my day every time I saw him in the hallways of the astronomy department building. He is one of the nicest people I have ever had the privilege of meeting. His astrophysical acumen never ceased to amaze and his sense of joy about everything around him was infectious, I will miss him dearly. Mila and I send our sincere condolences to Cynthia and the rest of his family.

The description captured the Bill I knew so well as a grad student back in the 70s. If we happened to be on the evening bus together, he would sometimes invite me to dinner spontaneously. He made hydro fun and funny. At one point, he was linearizing an equation, crossing out c, G, and 2pi (!). One student objected to the latter, and he said, "this is astronomy; no one will get killed."