Study of the changes of the distribution of spectral properties of S-type asteroidal dynamical families with age: Mean values and Skewness.

EDUARDO TELLO-HIANCA; MARIO MELITA

VIRTUAL

Congreso; European Planetary Science Congress; 2021

European Planetary Science Society

orrelations between family-age and the slope of the spectral distribution, caused by the cummulative effect of cosmic irradiation,have been established for S-type dynamical families by many authors.We noticed that if there is a variety in the primordial surfacecomposition, then the typical timescale that determines the speed ofthis evolution is bound to have a range of values. Consequently, asthe mean value of the color distribution tends to steeper (redder)slopes, a progressive skewness in this distribution should develop.Using the SDSS-MOC-4 and NEOWISE R-albedos, we cross-examined theS-type families as defined by both Nesvorny et al. (2015) and Spottoet al (2015) and retained only members with albedos and colors in thecharacteristic range of the S-types. We corroborate the colorevolution with age and we compare our results with previousestimations. Using only the "true S-type" family members, we also finda significative correlation between some skewness estimationparameters and age. Our results offer additional evidence of theeffects of cosmic-radiation on asteroidal surfaces and provide posiblenew relations to determine the age of S-type dynamical families.orrelations between family-age and the slope of the spectral distribution, caused by the cummulative effect of cosmic irradiation,have been established for S-type dynamical families by many authors.We noticed that if there is a variety in the primordial surfacecomposition, then the typical timescale that determines the speed ofthis evolution is bound to have a range of values. Consequently, asthe mean value of the color distribution tends to steeper (redder)slopes, a progressive skewness in this distribution should develop.Using the SDSS-MOC-4 and NEOWISE R-albedos, we cross-examined theS-type families as defined by both Nesvorny et al. (2015) and Spottoet al (2015) and retained only members with albedos and colors in thecharacteristic range of the S-types. We corroborate the colorevolution with age and we compare our results with previousestimations. Using only the "true S-type" family members, we also finda significative correlation between some skewness estimationparameters and age. Our results offer additional evidence of theeffects of cosmic-radiation on asteroidal surfaces and provide posiblenew relations to determine the age of S-type dynamical families.