The collapsing star Amargosa in 2371.
Amargosa (AM-ahr-GOH-suh) is the primary star of the Amargosa system, studied by a Federation observatory where Dr. Tolian Soran developed his trilithium weapon. From the observatory, Soran launched the weapon into Amargosa in 2371 and collapsed the star, producing a level-12 shockwave that destroyed everything in the system.
The collapse of Amargosa altered gravitational forces throughout the sector, forcing the USS Bozeman to make a minor course correction. The same forces altered the flight path of the Nexus ribbon as Soran had planned, as part of his attempt to bring the ribbon to a planet. (Star Trek: Generations)