논문 상세보기
THE GEOMETRIC ALBEDO OF (4179) TOUTATIS ESTIMATED FROM KMTNET DEEP-SOUTH OBSERVATIONS KCI 등재 SCOPUS
- 언어ENG
- URLhttps://db.koreascholar.com/Article/Detail/383957
pp.71-82
We derive the geometric albedo of a near-Earth asteroid, (4179) Toutatis, to investigate its surface physical conditions. The asteroid has been studied rigorously not only via ground-based photometric, spectrometric, polarimetric, and radar observations but also via in situ observation by the Chinese Chang'e-2 space probe; however, its geometric albedo is not well understood. We conducted V-band photometric observations when the asteroid was at opposition in April 2018 using the three telescopes in the southern hemisphere that compose the Korea Microlensing Telescope Network (KMTNet). The observed time-variable cross section was corrected using the radar shape model. We nd that Toutatis has a geometric albedo pV = 0:185+0:045 -0:039, which is typical of S-type asteroids. We compare the geometric albedo with archival polarimetric data and further nd that the polarimetric slope{albedo law provides a reliable estimate for the albedo of this S-type asteroid. The thermal infrared observation also produced similar results if the size of the asteroid is updated to match the results from Chang'e-2. We conjecture that the surface of Toutatis is covered with grains smaller than that of the near-Sun asteroids including (1566) Icarus and (3200) Phaethon.
1. INTRODUCTION
2. OBSERVATION AND DATA REDUCTION
3. DERIVATION OF THE GEOMETRIC ALBEDO
3.1. Correction for Rotation and Distances
3.2. Radiance Factor and Geometric Albedo
4. DISCUSSION
4.1. Sources of Uncertainties
4.2. Comparison with Flyby Observations
4.3. Comparison with Thermal Infrared Studies
4.4. Comparison with Polarimetric Studies
5. CONCLUSIONS
REFERENCES
