I'm a big fan of Mathematica even though all commercial software irritates me on some level (transparency, cost, and licensing annoyance). As a result I follow

I'm a big fan of Mathematica even though all commercial software irritates me on some level (transparency, cost, and licensing annoyance). As a result I follow Stephen's blog and sometimes they come off as a little self serving and grandiose, but this one was terrific to me as a non physicist in better learning the history and challenges of all of this. It's hard to understand sometimes that celestial mechanics is simply not a "solved" problem these days.