Lemma II was the second planet in the Lemma planetary system. A colony was located on this planet.
In 2368, this planet was the intended destination of an experimental soliton wave generated from Bilana III, three light years away. The Lemma II facility was intended to generate a particle scattering field to disperse the wave. However, the wave destabilized and accelerated out of control, threatening to destroy most of Lemma II. Fortunately, the USS Enterprise-D disrupted the wave before it arrived. (TNG: "New Ground")