Accurate absolute magnitudes for Kuiper belt objects and Centaurs

Accurate absolute optical magnitude values ( H V and H R ) for Kuiper belt objects (KBOs) and Centaurs are becoming increasingly important as observations in other wavelengths, particularly SIRTF thermal infrared measurements, become available for large samples of objects. We present accurate H V and H R values for 90 KBOs and Centaurs, based on our published optical photometry. We find that our H V values are in good agreement with those available from the European photometric survey of minor bodies in the outer Solar System. Comparison with H V values from the JPL Horizons database and the Minor Planet Center database shows that these sources are systematically brighter than ours by about 0.3 mag.