Pelloris asteroid field
The Pelloris asteroid field was an asteroid field rich in nitrium that was located near Tessen III. 

In 2368, an asteroid from the Pelloris field threatened Tessen III and was destroyed by the . However, a metal parasite from the destroyed asteroid infested the Enterprise and severely distorted the ship's systems, including life support. The Enterprise then returned to the field and lured the parasite back to the field with a particle beam containing nitrium directed on the field. ()

Asteroid belts