I don't know about that one, but it wouldn't surprise me either way (still in Lisp or reimplemented/replaced by something else) since such things seem to be hit-and-miss and unless you do some digging it's probably unlikely many programmers of such systems check HN... But for a comparatively old government project in Common Lisp, there's at least one, SPIKE (https://www.stsci.edu/scientific-community/software/spike), that was developed for planning and scheduling the Hubble telescope (and other projects) and is still in use for the JWST (https://www.stsci.edu/contents/newsletters/2018-volume-35-is...).