Hobus

Hobus was a star with an associated star system located within the Romulan Star Empire's borders. 

History
In 2387 Hobus went supernova, releasing a shockwave that propagated through subspace at faster-than-light speeds and destroyed all in its path, obliterating the Romulan system, among others, and killing billions of people. The shockwave was only stopped by a daring mission by Ambassador Spock, who piloted his starship Jellyfish into the heart of the inferno to detonate a red matter device, consuming the star's fury with an artificial black hole. Spock was then trapped in the singularity, along with the Narada, and was presumed deceased, though in reality both vessels had been sent back to 2233 in a massive temporal incursion that created an alternate reality. 

The remnants of the supernova became known as the Hobus Nebula. 

The destruction of Romulus in the supernova set off a long-running political and humanitarian crisis in Romulan space that resulted in the Tal Shiar attempting to take over rulership of the Empire, as well as in the eventual formation of the Romulan Republic. 

In 2409 Romulan Republic agents discovered that Tal Shiar agents Taris and Hakeev, operating at the behest of the Iconians, had in fact artificially induced the supernova. This revelation set off a renewed round of civil war in the Empire and a number of planets seceded in protest. Praetor Velal tr'Hrienteh eventually won rulership of the Empire and sued for peace with the Republic. (Ahrir'fvahir Mnean?; ; )

Known casualties of the supernova

 * House Thavrau, including Iliana t'Thavrau and Sindari t'Thavrau, on Romulus and Sheratan VII