51640

51640 (2002 AV10) is a stony asteroid orbiting the Sun in the inner region of the asteroid belt. It was first observed on 20 September 2002 by the Lincoln Near-Earth Asteroid Research (LINEAR) project at the Lincoln Laboratory’s Experimental Test Site in Socorro, New Mexico. The discoverer, a team of automated survey scientists, recorded a preliminary magnitude of 18.2 and issued a provisional designation before the object received its permanent number from the Minor Planet Center in 2021. No formal name has yet been proposed for 51640.

The asteroid has a semi-major axis of 2.21 astronomical units, an eccentricity of 0.12, and a perihelion distance of 1.94 AU and an aphelion of 2.48 AU. Its orbital period is approximately 3.30 years (1,205 days). Inclination relative to the ecliptic is 4.6 degrees, placing it modestly between the orbital planes of the outer main belt and the inner Mars-crossing region. Photometric studies indicate a rotation period near 5.7 hours with a brightness amplitude of about 0.15 magnitudes, suggesting a relatively spherical shape. The asteroid’s albedo is determined to be around 0.18, implying a diameter of roughly 4.5 kilometres assuming a standard absolute magnitude of 14.7.

Spectral analysis classifies 51640 as an S-type asteroid, consistent with the composition of the Eunomia family. The classification is based on visible and near-infrared spectroscopic data that exhibit silicate absorption features at 1 µm and 2 µm. No satellites or significant mass loss are detected. Continued observations using ground-based telescopes and the Gaia mission aim to refine its orbit and physical characteristics.

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