About 170 Starshield satellites built by SpaceX for the US government's National Reconnaissance Office (NRO) have been sending signals in the wrong direction, a satellite researcher found. The SpaceX-built spy satellites are helping the NRO greatly expand its satellite surveillance capabilities, but the purpose of these signals is unknown. The signals are sent from space to Earth in a frequency band that's allocated internationally for Earth-to-space and space-to-space transmissions. There have been no public complaints of interference caused by the surprising Starshield emissions.