The name of a star that went nova on stardate 5943.7 (2269), destroying its only planet, a Class-M world named Sarpeidon whose inhabitants fled to safety via a time portal.

At that time, the remains of Beta Niobe became temporarily linked with a newborn star named Amphion in a parallel "negative" universe composed primarily of antimatter. By stardate 6770.3, about a year later, Beta Niobe still existed as a highly dangerous stellar remnant. At that time the U.S.S. Enterprise inadvertently passed through the portal created by this transdimensional link, while attempting to prevent a small scout ship piloted by Karla Five from racing to its presumed destruction within the Beta Niobe stellar remnant.