Beta Niobe
Beta Niobe was the primary of an inhabited planetary system in the Alpha Quadrant. 

By the 2250s, the civilization in this star's system had become warp-capable and had or was in the process of being inducted into the . 

In 2259, the location of this star was labeled on a stellar cartography chart that was seen on the 's ready room viewscreen. This star's symbol had a blue color, indicating that it was affiliated with the . () 

This star went supernova in 2269, destroying itself and its only planet, Sarpeidon. () The star occupied the same space as the parallel antimatter universe star, Amphion. () 

In 2293, the location of Beta Niobe in the Milky Way Galaxy was labeled in a star chart that was in Captain James T. Kirk's quarters aboard the . (, okudagram)

In 2399, the location of Beta Niobe was labeled in a Federation star chart that was in Fleet Admiral Kirsten Clancy's office at Starfleet Headquarters. This star was located in neutral space. () 

In 3189, the location of Beta Niobe was denoted on a holographic star chart of the galaxy at Federation Headquarters. ()

History 
In 2269, hours before the star went nova, the  arrived to warn the native species of Sarpeidon of their impending doom. However, they found that all the inhabitants had evacuated, using a time portal known as the Atavachron, into various eras of the planet's past. ()

While en route to planet Babel in 2270, the Enterprise passed near Beta Niobe. They detected an alien ship racing for the center of the Beta Niobe nova at warp 36. The Enterprise attempted to tractor the ship in an effort to prevent it from its apparent suicidecourse. Both ships were taken into the center of the nova where they passed through into the parallel antimatter universe. ()

By the late 24th century, the Beta Niobe Nebula had formed around the remnants of the star. ()

Appendices

Background information 
There have been four conflicting accounts on the location of Beta Niobe. While all the accounts are canon, we assume the location depicted in the  star chart was the correct one and retconned the previous statements, as it was the latest of the accounts.

 The first is from the  episode "All Our Yesterdays" where Spock states Beta Niobe to be millions of light years away from . This distance figure suggests Beta Niobe was in another galaxy. 
 The second account is the large star chart table in the  episode "The Counter-Clock Incident" which displays the position of Beta Niobe in relation to Earth in the Milky Way Galaxy. The graphic depicts Beta Niobe on the other side of the galaxy approximately 50 thousand light years away from Earth in what is later on in Star Trek established to be the border region of the Delta and Gamma Quadrants.
 The third account was from the star chart "The Explored Galaxy" that was first seen in the  episode  of . The chart depicted Beta Niobe close to Ariannus and as far away from Earth as the Romulan Neutral Zone for example. The chart, first seen chronologically in Star Trek VI: The Undiscovered Country, set in 2293, was also seen in several Star Trek: The Next Generation and  episodes set in the 24th century.
 The fourth account was from a star chart seen in the office of Fleet Admiral Clancy in . This set Beta Niobe in the Alpha Quadrant.

External links 
 
 
 

de:Beta Niobe
it:Sistema Beta Niobe
ja:ベータ・ニオベ
nl:Beta Niobe
Stars