While playing FTL, I have suddenly gained information on the sector without having Long-Range Scanners or having paid a mercenary for a scouting report. IE, I can see environmental hazards and potential ship locations.
It has happened a few times, on different playthroughs. When it happens, it lasts for the duration of the sector, and then goes away.
Is there an event (other than paying mercs to scout), or something else that triggers this?