Follow-up observations for the Asteroid Catalog using AKARI Spectroscopic Observations

TL;DR

This study uses spectroscopic and physical data to classify asteroids from the AKARI catalog, revealing compositions compatible with water ice and dust, and demonstrating the value of combined observational methods for surface analysis.

Contribution

It integrates spectroscopic data with physical observations to classify asteroids and constrain their surface compositions, advancing asteroid taxonomy and analysis methods.

Findings

Certain C-, Cb-, B-type, dark X-, and D-type asteroids have water ice and dust signatures.

Combining taxonomy with physical data improves surface material constraints.

Supports previous hypotheses about C-complex asteroid compositions.

Abstract

In the 1-2.5 micron range, spectroscopic observations are made on the AcuA-spec asteroids, whose spectra were obtained in a continuous covered mode between 2.5-5.0 micron by AKARI. Based on the Bus-DeMeo taxonomy (DeMeo et al. 2009, Icarus, 202, 160), all the AcuA-spec asteroids are classified, using the published and our observational data. Additionally, taking advantage of the Bus-DeMeo taxonomy characteristics, we constrain the characteristic each spectral type by combining the taxonomy results with the other physical observational data from colorimetry, polarimetry, radar, and radiometry. As a result, it is suggested that certain C-, Cb-, B-type, dark X-, and D-complex asteroids have spectral properties compatible with those of anhydrous interplanetary dust particles with tiny bright material, such as water ice. This supports the proposal regarding the C-complex asteroids (Vernazza et al. 2015, ApJ, 806, 204; 2017, AJ, 153, 72). A combination of the Bus-DeMeo taxonomy for AcuA-spec asteroids and the presumptions with other physical clues such as the polarimetric inversion angle, radar albedo, and mid-infrared spectroscopic spectra will be beneficial for surface material constraints, from the AcuA-spec asteroid observations.