Gravimetric interferences were phenomena in space that could make plotting a course rather difficult. Navigating through a globular cluster like the Amargosa Diaspora can be complicated by gravimetric interferences. When the USS Enterprise-D was examining the Amargosa Diaspora in 2369, Commander William T. Riker assisted Ensign Sariel Rager in plotting a course through the clusters and showed her how to compensate for gravimetric interference. (TNG: "Schisms" )