Analysis of landing site candidates for system-level technical studies

JAXA Supercomputer System Annual Report February 2025-January 2026

Report Number: R25EB0101

Subject Category: Space Exploration

Responsible Representative: Hiroyuki Sato, Associate Senior Researcher, Institute of Space and Astronautical Science
Contact Information: Hiroyuki Sato(sato.hiroyuki@jaxa.jp)
Members: Hiroka Inoue, Shinichi Kinoshita, Risa Miyazaki, Shingo Nanbu, Hiroyuki Sato, Mitsuo Yamamoto

Abstract

To generate fundamental data for examining landing and traversal routes in future lunar landing missions through surface spectral analysis, identification of illuminated areas or regions with feasible Earth–Moon communication, and thermal environment simulations.

Reference URL

N/A

Reasons and benefits of using JAXA Supercomputer System

High-precision corrections of the observation locations for spectral data obtained by Kaguya's Spectral Profiler, illumination and communication simulations for the lunar polar regions using ray-tracing, and lunar surface thermal environment simulations using the commercial software COMSOL were conducted. Processing these datasets—each of which involves terabyte-scale data volumes—or performing high‑resolution calculations requires substantial computational resources, making the use of the JSS multi-core parallel computing system indispensable.

Achievements of the Year

In JAXA's lunar landing mission, we were able to provide the project team with the results of sunlight and communications simulations that form the basis for operational planning. In addition, we completed test runs of large-scale computations required for SP data position correction and thermal environment simulations, and obtained information on the constraints and other conditions necessary for proceeding with the next phase.

Publications

N/A

Usage of JSS

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: Manual parallelization by own script
Number of Processes: 12 - 36
Elapsed Time per Case: 5 Hour(s)

JSS3 Resources Used

Fraction of Usage in Total Resources*1(%): 0.07

Details

Please refer to System Configuration of JSS3 for the system configuration and major specifications of JSS3.

Computational Resources
System Name	CPU Resources Used (Core x Hours)	Fraction of Usage*2(%)
TOKI-SORA	0.00	0.00
TOKI-ST	503751.12	0.52
TOKI-GP	0.00	0.00
TOKI-XM	0.00	0.00
TOKI-LM	330.33	0.02
TOKI-TST	0.00	0.00
TOKI-TGP	0.00	0.00
TOKI-TLM	0.00	0.00

File System Resources
File System Name	Storage Assigned (GiB)	Fraction of Usage*2(%)
/home	0.00	0.00
/data and /data2	51200.00	0.34
/ssd	30720.00	1.87

Archiver Resources
Archiver Name	Storage Used (TiB)	Fraction of Usage*2(%)
J-SPACE	0.00	0.00

*1: Fraction of Usage in Total Resources: Weighted average of three resource types (Computing, File System, and Archiver).

*2: Fraction of Usage：Percentage of usage relative to each resource used in one year.

ISV Software Licenses Used

ISV Software Licenses Resources
	ISV Software Licenses Used (Hours)	Fraction of Usage*2(%)
ISV Software Licenses (Total)	0.00	0.00

*2: Fraction of Usage：Percentage of usage relative to each resource used in one year.