Tambor Beta-6 is a white dwarf star.
After taking control of the USS Enterprise-D in 2370, a network of emergent circuit nodes took the ship to Tambor Beta-6 (a.k.a. "Vertiform City"), where they used a modified tractor beam to collect vertion particles from the star. Unfortunately, the supply of vertions from the star was insufficient for the nodes to complete the creation of an emergent life-form, and so they turned the ship towards the Cordannas system. (TNG: "Emergence")