141 Lumen is a dark (C-type), large rocky asteroid 130 km in diameter orbiting in the main belt near the Eunomia family of asteroids. It is not, however, physically related to the group, being of the wrong spectral class. Yet, NASA continues to categorize it as a main-belt asteroid.
Richard P. Binzel and Schelte J. Bus further added to the knowledge about this asteroid in a light-curve survey published in 2003. This project was known as Small Main-belt Asteroid Spectroscopic Survey, Phase II or SMASSII, which built on a previous survey of the main-belt asteroids. The visible-wavelength (0.435–0.925 micrometre) spectra data was gathered between August 1993 and March 1999.
Lightcurve data has also been recorded by observers at the Antelope Hill Observatory, which has been designated as an official observatory by the Minor Planet Center.