Sentinel Six
From Tardis Wiki, the free Doctor Who reference
Sentinel Six was a robot security satellite in orbit around Earth. It was controlled from Sea Base 4.
In 2084, it encountered the TARDIS and demanded that they transmit the proper security code. Eventually, it fired at the TARDIS, but it did no damage. Afterwards, it reported to the Sea Base that it fired at a UFO which then disappeared. (TV: Warriors of the Deep)
