NLR190 is a spherical harmonic model to degree and order 24 based on approximately 5 million Eros radii collected by the NLR through day 190, year 2000. Because of its deviation from sphericity, on Eros one degree varies from about 54 to 307 m. This ellipsoid fits the observed shape of Eros as described to NLR190 to 1028 in an RMS sense. This is not a very good fit due to the fact that Eros deviates significantly from a simple ellipsoidal shape.
Deviations are due to collisions, craters, etc.