Remembering Bill Paxton
16 Aug 2025My friend and colleague Bill Paxton died on July 23, 2025. In retirement Bill found himself as an accidental astrophysicist and my own path was fortunate enough to have intersected that segment of his life.
During the summer of 2008 I heard about some new stellar evolution software being developed at KITP in Santa Barbara. I installed it and emailed the author with some comments and questions. In response to my message, Bill wrote:
You’re one of the first brave souls to try to use mesa, so it will be a learning process for both of us!
And wonderfully, for the next 13 years, it was. Before I left astrophysics in 2021, collaboration with Bill in some form or another was a near-constant part of my career. We exchanged thousands of emails and spent many hours working together during my visits to KITP.
Bill liked writing software. Bill was good at writing software. Bill was fast at writing software. A big part of working with Bill was simply keeping up with Bill! Someone would tell Bill something hadn’t been done (or sometimes couldn’t be done) and he’d take that as a challenge and then go off and do it. I will consider myself fortunate to maintain a fraction of Bill’s curiosity and drive.
In this photo from 2016, I (left) am wearing one of Bill’s autographed MESA baseball caps, as Lars Bildsten (center) prepares to hand out more, and Bill Paxton (right) solemnly looks on.
Bill shared this video clip in a context now lost to me. But it has remained in my browser bookmarks and I think of him every time I stumble across it.
There is a time for everything, a time to summon and a time to say goodbye.