Been almost 15 years since I was at the Lab but I don’t recall Lisp being at all popular. And I started there as a Perl & PHP developer before transitioning into Java.
The original article was written about 20 years ago and he says that by 1999 lisp was already falling out of favor (if it had ever been in favor). So, 15 years ago (2008?) would've been almost a decade after that.
I started at JPL in 2002 and worked with dozens of groups. Including many folks who had been at JPL since the 70s. No one ever talked about Lisp. I remember helping a former team member who had transitioned to ground systems port an old Mars Rovers Motif/Xt app to Qt (2 or 3?) on Linux. Blew his mind how much performant Qt was on the same hardware and with simpler code. He only ever mentioned being forced to use Ada for a few years and then being forced to port the code to C/C++ a budget cycle later. Probably around 2006. He had been at the lab since the 80s.
But to be fair to the TFA’s author, prior to about 2007 when we got our first CIO, we could literally use almost any technology as long as it wasn’t illegal and wouldn’t get NASA, JPL, or CalTech in trouble. I ran databases & web sites with public IPs, ran myPHPAdmin, phpNuke, QTSS hosts and bunch of other crazy stuff with public IPs.
