Memory Alpha
Memory Alpha
Multiple realities
(covers information from several alternate timelines)
For the rogue Federation agency, please see Section 31.

Sector 31 was a region of space in the Beta Quadrant. A segment of the Romulan Neutral Zone was located in this sector.

In 2364, communication with Federation starbases in this sector ceased as of stardate 41903.2. The identity of the assailant that had destroyed the bases was unknown at the time. (TNG: "The Neutral Zone") It was later on determined that the Borg were responsible for the attack. (TNG: "Q Who")

In the alternate 2259, this sector was labeled on a map of the Alpha Quadrant. This map was in a collection of graphics and video media that were seen on a powerwall in the offices of Admirals Christopher Pike and Alexander Marcus at Starfleet Headquarters. (Star Trek Into Darkness)

This sector's quadrant of origin is inferred from it containing a section of the Romulan Neutral Zone. This zone was canonically located in the Beta Quadrant in the Star Trek: Picard episode "The Impossible Box".
The map showing the location of Sector 31 in the alternate reality can be seen in the video "Star Trek: Into Darkness" – User Interface VFX at [1]
According to Star Trek: Star Charts (p. 66), this sector was also known as the Glintara sector.

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