FGC 47

From Memory Alpha, the free Star Trek reference.

FGC 47 is a nebula composed primarily of helium, hydrogen, and trionium, that is centered around a neutron star.

The USS Enterprise-D investigated the nebula in 2368 and found it to be populated by non-corporeal beings and filled with a dense web of plasma energy strands. The entities living in the nebula viewed Enterprise's energy systems as far purer than those normally present in the nebula on which they "fed". As a result they began draining energy from the starship, which was slowed in its attempts to depart the nebula by the presence of the energy strands.

During the investigation of the nebula, Geordi La Forge attempted to convince Data that the formation should be named La Forge's Nebula, though Ensign Daniel Sutter preferred Sutter's Cloud. (TNG: "Imaginary Friend")