1996 TQ66 has a very red surface color (RR) in the visible part of the spectrum, with B−V and V–R color indices of 1.190±0.020 and 0.660±0.030, respectively, for a combined B−R magnitude of 1.85.[4][6][7] A red surface color is typically associated with the presence of tholins, polymer-like organic compounds, formed by long exposures to solar and cosmic radiation.
Rotation period
In 1999, results of a photometric survey of Kuiper belt objects by Romanishin and Tegler were published in the Journal Nature. For 1996 TQ66, a brightness variation of no more than 0.22 in magnitude could be determined, which is indicative of a modestly irregular shape.[7][11] As of 2021[update], no rotational lightcurve for this object has been obtained from photometry. The body's rotation period, pole and actual shape remain unknown.[3][7]
Diameter and albedo
Based on a generic magnitude-to-diameter conversion, 1996 TQ66 measures approximately 185 kilometers (110 miles) in diameter, for an assumed albedo of 0.9 and an magnitude of 7.[4][12] According to Mike Brown, who estimates a mean-diameter of 186 km (120 mi), the object is too small for being considered a dwarf planet candidate ("probably not").[13]