Size-Dependent Fresh Surface Signatures in Asteroid Families: Observational Evidence from Dual-Band Albedo Analysis

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 ∼ 3.4) and comprehensive error propagation analysis (median V-Dominance Index (VDI) uncertainty ∼0.13). 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 𝑝V/𝑝IR > 1.2 (99.8th percentile of the main-belt distribution). Among tested parameters, family population size (𝑁) emerged as the dominant correlate of VDI across both silicaceous (S-complex: 𝑟s = 0.58) and carbonaceous (C-complex: 𝑟s = 0.44) taxonomic types, with fullsample correlation 𝑟s = 0.476 (𝑝 = 4.31 × 10−10). This correlation survived Monte Carlo permutation tests, binomial null model validation, and age-matched contrast analyses, and heliocentric independence tests (partial correlation 𝑟partial = 0.488). Percentile sensitivity analysis (Δ𝑟s = 0.38 across 95th–99.8th 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 (𝑝 < 10−4), 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.

Keywords

• Asteroid families
• Space weathering
• Collisional resurfacing

References

1. Binzel R. P., et al., 2010, Nature, 463, 331 google scholar
2. Bottke W. F., Durda D. D., Nesvorný D., Jedicke R., Morbidelli A.,Vokrouhlický D., Levison H. F., 2005, Icarus, 179, 63 google scholar
3. Broz M., et al., 2024, Astronomy & Astrophysics, 689, A183 google scholar
4. Brunetto R., et al., 2015, in Michel P., DeMeo F. E., BottkeW. F., eds, Asteroids IV. University of Arizona Press, Tucson, pp 597–616 google scholar
5. Cook R. D., 1977, Technometrics, 19, 15 google scholar
6. DeMeo F. E., Binzel R. P., Slivan S. M., Bus S. J., 2009, Icarus, 202,160 google scholar
7. Delbo M., et al., 2017, Science, 357, 1026 google scholar
8. Durda D. D., Bottke W. F., Nesvorný D., Enke B. L., Merline W. J., google scholar Asphaug E., Richardson D. C., 2007, Icarus, 186, 498 google scholar

9. Lantz C., Brunetto R., Barucci M. A., Fornasier S., Baklouti D., Binzel R. P., DeMeo F. E., 2018, Icarus, 302, 10 google scholar
10. Loeffler M. J., Dukes C. A., Baragiola R. A., 2009, Journal of Geophysical Research: Planets, 114, E03003 google scholar
11. Mainzer A., et al., 2011, The Astrophysical Journal, 731, 53 google scholar
12. Masiero J. R., et al., 2020, The Planetary Science Journal, 1, 9 google scholar
13. Nesvorný D., Brož M., Carruba V., 2015, in Michel P., DeMeo F. E.,Bottke W. F., eds, , Asteroids IV. University of Arizona Press,Tucson, pp 297–321 google scholar
14. Parker A., Ivezic Z., Juric M., Lupton R., Sekora M. D., Kowalski A. ,2008, Icarus, 198, 138 google scholar
15. Richardson J. E., Melosh H. J., Greenberg R. J., 2004, Science, 306, 1526 google scholar
16. Sasaki S., Nakamura K., Hamabe Y., Kurahashi E., Hiroi T., 2001,Nature, 410, 555 google scholar
17. Sergeyev A. V., Carry B., 2021, Astronomy & Astrophysics, 652, A59 google scholar
18. Spoto F., Milani A., Knežević Z., 2015, Icarus, 257, 275 google scholar
19. Usui F., et al., 2011, Publications of the Astronomical Society of Japan, 63, 1117 google scholar
20. Vernazza P., Binzel R. P., Rossi A., Fulchignoni M., Birlan M., 2009, Nature, 458, 993 google scholar
21. Willman M., Jedicke R., Moskovitz N., Nesvorný D., Vokrouhlický D., Mothé-Diniz T., 2010, Icarus, 208, 758 google scholar