1. 太陽系始原天体の突発現象 石黒正晃（ソウル大学） in collaboration with
Image credit: EAO
石黒正晃（ソウル大学）
in collaboration with
Hongu Yang, Yoonyoung Kim, Yuna Kwon, Mingyeong Lee, Yoonsoo Park
ワークショップ：地上赤外線観測による太陽系内天体の観測戦略（2016年9月7日）

2. Comet of 67P/Churyumov-Gerasimenko
1. Limitation of in-situ observations
Asteroid Itokawa
Comet of 67P/Churyumov-Gerasimenko
Credit: ESA/Rosetta team, JAXA/Hayabusa team

3. 1-1. Comets and dust mantle
Dust and Gas
dust mantle
Thermal skin depth several tenth cm (Park, Ishiguro, Usui+, in preparation)

4. SW have been observed only <~1um layers on dust grains
1-2. Asteroids and space weathering
Noguchi et al. Science, 333, 6046, 1121 (2011)
SW have been observed only <~1um layers on dust grains

5. 2. Transient Events Impacts（Cratering or Catastrophe）
Rotational Breakup
Cometary Outbursts

6. 2-1. Impact (Cratering) (596)Scheila 50° 85° 10°
Ishiguro et al. ApJ 741, 1, L24, 5 (2011)

7. 2-1. Impacts (Catastrophe)
Jewitt et al. Nature 467, 7317, 817, 2010
Kim, Ishiguro, Michikami and Nakamura (in preparation)

8. 2-2. Rotational Breakup Jewitt et al. ApJ 784, L8 (2014)

9. 2-3. Cometary Outbursts
Ishiguro, Jewitt, Hanayama et al. ApJ 787, 55 (2014)
Ishiguro, Kuroda, Hanayama et al. (AJ accepted)

10. 2-4. The Frequencies Impacts among asteroids Catastrophe： 1.0 /yr*
Cratering：　 /yr
Rotational breakup
Asteroids >100-m: 10 /yr*
Cometary outbursts
Ikeya-Murakami class: 1.5 /yr**
* Jewitt, Hsieh & Agarwal, Asteroids IV221 (2015)
** Ishiguro, Kuroda, Hanayama et al. AJ (accepted)

11. 3. Expectations for TAO Unique instruments (SWIMS/MIMIZUKU)
Advantage of the location (Synergy with LSST)
Flexible operations (ToO and daytime operations)

12. 3-1. Synergy of TAO with other facilities
KMTNet (Operated since 2015)
LSST (After 2020?)
Three 1.6-m telescopes in the southern hemisphere
Images from

13. 3-3. Flexible Operation Importance of ToO Observations
Early follow-up observation within 2-7 days
(in case of HST/DDT, it requires several weeks)
Importance of Daytime Observations
Unexplored field

14. Simulation Images for STEREO-A image (ephemeris from JPL/Solar System Dynamics)
Convolved with PSF (FWHM=70”)
dust trail
very fresh micron particles
fresh dust tail
dust trail
Jewitt et al. ApJ, 77, L36 (2013)
0.1<b<1, DT=2day, Vb=1=800 m/s
10-4<b<1, DT=1100day, Vb=1=800 m/s