Sector 87 is a relatively untravelled region of space and the site of a number of mysterious and shady reports.
In 2261, a salvage merchant called Isaac claimed to have found an abandoned Starfury floating dead in Sector 87. He later sold parts of it to a trader on Zafran VII.
Sector 87 by 20 by 42 was an area Susan Ivanova and Marcus Cole searched for signs of the last remaining First Ones, having seen reports of something "godlike" sighted in the region.
Sheridan later ordered Marcus to take three White Stars out to Sector 87, shoot a bunch of rocks and come back, as part of a ruse to convince the League of Non-Aligned Worlds they needed White Star protection.