2021/04/21 by Pierre Beck, Olivier Poch
Earth and Planetary Sciences · Environmental Science · Physics and Astronomy · #Albedo (alchemy) #Asteroid #Asteroid belt #Astro and Planetary Science #Astrobiology #Astronomy #Astrophysics #Chondrite #Cluster (spacecraft) #Computer science #Geology #Geology and Paleoclimatology Research #Isotope Analysis in Ecology #Meteorite #Physics #Population #Regolith #Sky #Space weathering #Texture (cosmology) #astro-ph.EP
paper · pdf · doi:10.1016/j.icarus.2021.114494
published as Icarus, 2021
openalex publication_date 2021/04/21 · arxiv created 2021/05/05 · arxiv updated 2021/05/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The Sloan Digital Sky Survey provides colors for more than 100 000 moving objects, among which around 10 000 have albedos determined. Here we combined colors and albedo in order to perform a cluster analysis on the small bodies population, and identify a C-cluster, a group of asteroid related to C-type as defined in earlier work. Members of this C-cluster are in fair agreement with the color boundaries of B and C-type defined in DeMeo and Carry (2013). We then compare colors of C-cluster asteroids to those of carbonaceous chondrites powders, while taking into account the effect of phase angle. We show that only CM chondrites have colors in the range of C-cluster asteroids, CO, CR and CV chondrites being significantly redder. Also, CM chondrites powders are on average slightly redder than the average C-cluster. The colors of C-cluster members are further investigated by looking at color variations as a function of asteroid diameter. We observe that the visible slope becomes bluer with decreasing asteroids diameter, and a transition seems to be present around 20 km. We discuss the origin of this variation and, if not related to a bias in the dataset - analysis, we conclude that it is related to the surface texture of the objects, smaller objects being covered by rocks, while larger objects are covered by a particulate surface. The blueing is interpreted by an increased contribution of the first reflection in the case of rock-dominated surfaces, which can scatter light in a Rayleigh-like manner. We do not have unambiguous evidence of space weathering within the C-cluster based on this analysis, however the generally bluer nature of C-cluster objects compared to CM chondrites could be to some extent related to space weathering.