493-30923 was a comet near the Romulan Neutral Zone. (Star Trek: Section 31)

In an alternate timeline, created by Christopher Pike avoiding his injury in 2266, the USS Enterprise under the command of Pike and the USS Farragut under the command of James T. Kirk attempted a pincer maneuver tactic to expose a Romulan Bird-of-Prey. However, upon clearing the comet, the Bird-of-Prey was not detected, instead appearing behind the Farragut, destroying it. (SNW: "A Quality of Mercy")

In 3196, this comet's position was labeled on a Federation star chart that displayed the warp dead zone created by the Omega-47 mine test, performed by the Venari Ral. This comet was located outside the affected region. (SA: "300th Night")