Star chart showing area where Diana was attacked.
The Diana was an Earth starship.
Sometime prior to 2364, the Diana was attacked. The location of this incident was marked in viewscreen readouts aboard the USS Enterprise-D on several occasions in 2364, in the form of star charts from the Enterprise library computer. (TNG: "The Naked Now", "The Last Outpost", "Conspiracy")
Background
The Enterprise computer's star chart was a drawing by Rick Sternbach that had originally been published, years earlier, on page 95 of the reference titled Spaceflight Chronology. This chart showed Federation commercial lanes and exploration routes in the 2090s, but no text attesting to this fact was included in the portion used onscreen, just the labeled names of the ship attack locations.