Japan Geoscience Union Meeting 2018

Presentation information

[EJ] Poster

P (Space and Planetary Sciences) » P-PS Planetary Sciences

[P-PS05] Lunar science and exploration

Wed. May 23, 2018 3:30 PM - 5:00 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Hiroshi Nagaoka(Waseda Univ.), Tomokatsu Morota(Graduate School of Environmental Studies, Nagoya University), Masaki N (名古屋大学宇宙地球環境研究所, 共同), Masahiro KAYAMA(Department of Earth and Planetary Material Sciences, Faculty of Science, Tohoku University)

[PPS05-P11] Characterization of Lunar Surface Environment at APPROACH Landing-site Candidate

*Keisuke Onodera1,2, Satoshi Tanaka2, Ken Goto2, Hiroaki Shiraishi2, Taichi Kawamura3,4, Ryuhei Yamada5, Hideki Murakami6, Yoshiaki Ishihara2, Masahiko Hayakawa2 (1.SOKENDAI (The Graduate University for Advanced Studies), 2.Institute of Space and Astronautical Science / Japan Aerospace Exploration Agency, 3.Institut de Physique du Globe de Paris, 4.National Astronomical Observatory of Japan, 5.University of Aizu, 6.Kochi University)

Keywords:APPROACH, Moon, Landing site selection, Internal structure

APPROACH (Advanced Penetrator Probe for a Challenge of Hard-landing) is a future lunar science mission which aims to investigate the internal structure of the Moon [1]. In this mission, a penetrator will be deployed on the Moon and observe seismic activities and heat flow. Generally, it is essential for almost all landing-missions to understand the surface environment of their landing-sites for successful touchdown. As for the Moon, recent missions (e.g. KAGUYA and LRO) obtained high-resolution imagery of lunar surface, and these data enabled us to evaluate the surface conditions.

To meet the science objectives of APPROACH [1], we selected a landing-site candidate using LROC Narrow Angle Camera (NAC) data, rock abundance map deduced from Diviner [2][3], Th map [4] and elevation map [5]. After the selection, we counted the boulders at the landing-site candidate to measure rock size-frequency distribution (RSFD).

We also simulated the deployment of a penetrator and estimated the probability of success (i. e. how many penetrators can successfully penetrate into subsurface). In the simulation, about 1 million rocks were randomly located within the error circle of the deployment. The size distribution of the rocks was given based on the RSFD we measured. Them, a penetrator was installed 1000 times. We carried out this operation 100 times and calculated the average and standard deviation of the probability of success. As a result, more than 99 % success was shown through the simulation.

In the presentation, we’ll show how the landing-site candidate was selected and what kind of analyses were demonstrated to evaluate the probability of success.

[1] Tanaka et al. (2018), Proc. Space Sci. Symp., 18th, Jan. 5-6, ISAS/JAXA.
[2] Bandfield et al. (2011), JGR, 116, E00H02.
[3] Bandfield et al. (2017), Icarus, 283, 282-299.
[4] Yamashita et al. (2012), EPSL, 353-354, 93-98.
[5] Araki et al. (2009), Science, 323, 897-900.

We’d like to appreciate JAXA Lunar and Planetary Exploration Data Analysis Group (JLPEDA) for providing necessary image data & analysis tools.