The Fine Guidance Sensor (FGS) on the James Webb Space Telescope, a mission-critical element designed and built in Canada, was used in tracking mode for the first time as part of the telescope’s 18 golden hexagonal mirror alignment process. On February 13, the Webb team performed “Line of Sight” testing that confirmed the FGS‘s ability to “lock on” to a specific guide star in tracking mode. This mode allows the FGS to transmit highly precise information to Webb’s positional system 16 times per second. The successful FGS operation is the latest in a series of smooth manoeuvres for the massive o…