The galvanic beam was an energy weapon UNIT owned that was capable of firing a powerful red laser as far as the Earth's atmosphere. Operating on galvanic radiation, the beam required an entire grounds team to monitor and prepare it for usage, with a designated armourer typically manning the controls to aim and fire it. The beam could easily destroy a satellite.
Kate Stewart received the Fourteenth Doctor's permission to fire it at a satellite the Toymaker was using the control the human race. However, the Toymaker killed the beam's ground staff and took control of it for himself. The Doctor confronted him and the Toymaker used the galvanic beam to kill him, forcing the Doctor to regenerate, although it accidentally caused a bi-generation instead, summoning the Fifteenth Doctor. (TV: The Giggle [+]Russell T Davies, Doctor Who 2023 specials (BBC One and Disney+, 2023).)