Size-Dependent Fresh Surface Signatures in Asteroid Families: Observational Evidence from Dual-Band Albedo Analysis
Year: 2026
Type: article
Abstract: The spectral evolution of asteroid surfaces reflects the competition between space weathering and impact resurfacing. While previous studies have focused primarily on age-dating, the role of family population size has remained largely unexplored. Here we tested whether population-dependent collisional activity affects observable surface properties by analyzing 154 asteroid families using NEOWISE thermal infrared photometry, employing a family-averaged statistical approach validated by independent AKARI observations (variance reduction factor โผ 3.4) and comprehensive error propagation analysis (median V-Dominance Index (VDI) uncertainty โผ0.13). We introduced the VDI as a statistical measure quantifying the incidence of extreme resurfacing signatures within families, operationally defined as the fraction of members with visible-to-infrared albedo ratios ๐V/๐IR > 1.2 (99.8th percentile of the main-belt distribution). Among tested parameters, family population size (๐) emerged as the dominant correlate of VDI across both silicaceous (S-complex: ๐s = 0.58) and carbonaceous (C-complex: ๐s = 0.44) taxonomic types, with fullsample correlation ๐s = 0.476 (๐ = 4.31 ร 10โ10). This correlation survived Monte Carlo permutation tests, binomial null model validation, and age-matched contrast analyses, and heliocentric independence tests (partial correlation ๐partial = 0.488). Percentile sensitivity analysis (ฮ๐s = 0.38 across 95thโ99.8th percentiles) demonstrated that VDI isolates rare resurfacing events detectable only at extreme thresholds. In families older than 2 Gyr, large populations maintained statistically significant fresh tails (๐ < 10โ4), whereas small populations were saturated. These results are consistent with model predictions where massive families experience elevated collisional resurfacing rates that counteract spaceweathering saturation, though alternative mechanisms cannot be excluded.
Source: Physics and Astronomy Reports
Author: Murat Kaplan
Institution: Akdeniz University
Language: English
Topic: Astro and Planetary Science
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7165017357