The Amargosa observatory was a Federation space station that was in service in the late 24th century. The observatory was located in orbit of the Amargosa star and was used for scientific research of it.
In 2371, the station had a complement of nineteen personnel, including an El-Aurian named Dr. Tolian Soran. With the help of the Klingon outlaw Duras sisters, he had secured trilithium stolen from the Romulans, planning to build a trilithium weapon, which is capable of stopping all nuclear reactions in a star, thereby causing its collapse.
The USS Enterprise-D answered a distress call of the observatory, which had been raided by Romulans, who were searching for their stolen trilithium. Only Soran survived the attack, who was rescued by an away team from the Enterprise, only to escaped its custody soon after to return to the station. Geordi LaForge and Lieutenant commander Data arrived to the station to investigate, and discovered Soran's secret laboratory where he kept the stolen trilithium. They were unable to stop Soran from using the weapon towards Amargosa star, capturing LaForge in the process.
After Soran launched his weapon, the star collapsed and the resulting level-12 shock wave destroyed the observatory, along with everything else in that solar system. (Star Trek Generations)
Background information
The interior of the station featured jewel button control panels, intercoms and graphic displays identical to those seen on the original USS Enterprise. This suggests either that the station was more than one hundred years old at the time of its destruction, or its computer systems were that old.
The model of the observatory was reused for the wormhole relay station in DS9: "Destiny".
In the video game adaptation of the movie, it is possible to avert Soran's plans and save the star and the station.