Department of Earth a n d Space Science

Department ofEarth and SpaceScience

Department of Earth andSpace ScienceHome Page

Overview

http://www.ess.sci.osaka-u.ac.jp/en

Scope of ScienceThe Department of Earth and Space Science, Graduate
School of Science of Osaka University, is a uniquedepartment established in 1995, aimed at developing a
new horizon in the research and education of earth andspace science from a physics-based perspective. The
principal goals of our department’s research activities
are to understand the extreme state of matter in space,including even life, and to decipher the many diverse
phenomena which occur in space, the planets and theEarth.
Our research and educational activities are conductedin eight groups based on Theoretical astrophysics, Xray astronomy, Infrared astronomy, Isotope
cosmochemistry, Earth and planetary physics, Solarsystem science, Soft matter physics, and Theoreticalcondensed-matter physics.
Our department focuses on fundamental physics as thebasis of Earth and Space science. This is why we aim
to conduct research and education in close
collaboration with the Department of Physics at theGraduate School of Science. Our department is always
open to talented researchers and students from a widevariety of fields, from physics to astronomy, earthscience, geology, mineralogy, chemistry, biology, andengineering.
The current student capacity is 28 for the Master's
course and 13 for the Doctoral course. Aftercompleting the course, students are active in a wide
range of fields, including not only universities andresearch institutes, but also general companies,government offices, and junior high and high schools.

The Department of Space and Earth Science focuseson the study of all things in the universe, which takeplace in the vast space-time of 13.8 billion years and13.8 billion light-years. In particular, our research andeducational activities are based on the four key
concepts of “space”, “earth and planets”, “matter”,
and “life”.
Of course, these four keywords are deeply related toeach other, as in “Earth in the Universe”, “Life on
Earth-like Planets”, “Material Evolution in theUniverse”, and “Materials in Extreme Planetary
Environments”, and the research content of eachresearch group will also span multiple fields. For
details, please see the following pages.

Scientific perspective
and social demands
The Department of Space and Earth Science is a newmajor that promotes in an interdisciplinary way thebasic sciences of Astronomy, Earth and Planetaryscience, Mineralogy, Geology, Chemistry, and Biology.
Today, as symbolized by natural disasters and global
environmental problems, it is highly required toharmonize human activities with “nature”, and there isa strong demand for people who can grasp the entire
picture of the universe and the earth and consider
logically while having a background in basic science.

Photograph of the entrance lobby. The wall design symbolizes theevolution of life and the birth of new Earth and Space Sciencefrom physics in the microscopic world. The floor is covered withPrecambrian granite (2.2 billion years old). The wall design
employs “stromatolite” formed by cyanobacteria (1.8 billion yearsold) and “wave-rippled sandstone” (1.2 billion years old). Let us
listen to the sound of Precambrian waves.

Graduate School of Science
2023-2024

Department of Earth a n d Space Science

DepartmentofEarth andSpace Science

Theoretical Astrophysics Group
Members

Kentaro NAGAMINE (Professor), Yoshiyuki INOUE (Associate Professor),
Shinsuke TAKASAO (Assistant Professor),
Isaac SHLOSMAN (Visiting Guest Prof.), Luca BAIOTTI (Adjunct Associate Prof.)

Home Page

http://astro-osaka.jp/[Research Area]
Our group covers a wide range of research
1) Structure formation and cosmology (large scale structure,
topics as described above, and our researchintergalactic medium, galaxy formation, dark matter)methods range from purely theoretical to2) Formation of astrophysical bodies (planets, stars, galaxies,
model building, numerical simulation, andsupermassive black holes)
observational data analysis.
3) High energy astrophysics (jets, black holes, cosmic-rays)
4) Astrophysical plasma, magneto-hydrodynamics, solar physics
5) Gravitational wave astronomy

Our universe was born 13.8 billion years ago in a massive
explosion known as the Big Bang. As the universe
expanded, large-scale structure and galaxies were formed,
and stars and planets were born and evolved within thesestructures. Various astrophysical phenomena in extreme
conditions took place; e.g., supernova explosions, blackhole formation, gravitational wave emission, gamma-ray
bursts, and acceleration of high-energy cosmic rays.

DepartmentofEarth andSpace Science

X-ray Astronomy GroupMembers

Hironori MATSUMOTO (Professor), Hirokazu ODAKA (Associate Professor),
Hirofumi NODA (Assistant Professor)

Home Page

http://www.ess.sci.osaka-u.ac.jp/en/about/research.html[Research Area]
1) Observational study of high-energy phenomena in the universe
3) Developments of instruments for high-energy astrophysics

Perseus cluster observed withthe Hitomi satellite

High-energy phenomena can be seen everywhere in the universe. For
example, a star explodes as a supernova at the end of its life, andleaves hot gas of a temperature of a few tens of millions of Kelvins.
The hot gas is called a supernova remnant, and it is luminous in Xrays. Black holes and neutron stars are thought to be born insupernovae. The gravity of these compact objects is extremely strong,
and they can emit X-rays when they accrete gas. Almost all galaxies
harbor a gigantic black hole at their centers. Some of them accreteinterstellar gas and emit X-rays as active galactic nuclei. Clusters ofgalaxies, the largest gravitationally bounded system in the universe,
are filled with hot gas, and they can be observed through X-rays.
We are performing X-ray observations of the hot universe using
X-ray astronomical satellites in the world such as Suzaku, Hitomi,MAXI, Chandra, XMM-Newton, and so on. We are also developing
new instruments for future applications such as X-ray CCD, MeV
gamma-ray detector, and X-ray mirror.

© Hitomi collaboration、JAXA、NASA、ESA、SRON、CSA

Graduate School of Science
2023-2024

Department of Earth a n d Space Science

DepartmentofEarth andSpace Science

Planetary Science Group
Members

Kentaro TERADA(Professor), Chihiro YAMANAKA (Associate Professor), Shoichiro
YOKOTA(Associate Professor), Kohei FUKUDA(Adjunct Assistant Professor)

Home Pages

http://planet.ess.sci.osaka-u.ac.jp［Research Area］
1）Origin and evolution of the Solar System.
2）Observation of the planetary environment by the laser
spectrometry3）Plasma measurements around planets and moons.
4）Development of the technique/instrument for a new frontierof planetary science.
To decipher the history of the Solar System, we focus on theorigin, evolution and current environment of our solar system
based on various experimental approaches. Mainly, we carryout precise isotopic analyses from hydrogen to uranium in
Apollo samples, other various meteorites and circum-stellar
dusts. We also conduct in-situ plasma observation including
mass analyses by spacecraft to study the environments aroundplanets and moons. The three-dimensional non-destructive
analysis using “muon” is also developed for the planetaryscience.

DepartmentofEarth andSpace Science

Planetary Materials Science Group
Members

Sho SASAKI (Professor), Osamu OHTAKA (Associate Professor),
Jun KIMURA (Assistant Professor)

Home Page

http://www.astroboy-jp.com/[Research Area]
1)
2)
3)
4)
5)

Formation and evolution processes of solid planets, satellites, and small bodies in the Solar System.
Phase transitions and physical properties of the Earth's deep interior (Ultra-high pressure experiments using synchrotron
radiation on the Earth's interior materials and their simulants).
Developments of instruments onboard spacecrafts (e.g., Martial moons explorer “MMX”, Jupiter icy moons explorer “JUICE”
and Rotorcraft landing mission on Titan “Dragonfly”) and techniques (e.g., in-situ observations under high pressure,
hyperspectral imager, and space weathering apparatus, etc.).
Dynamic process for atmospheric and geologic activity on planetary bodies.
Measurements of cosmic dust and development of dust accelerator.

Our research fields are, Earth and planetary material science, planetarygeology and physics, and Solar System explorations by telescopes andspacecrafts. Solar-system bodies have wide varieties on their surfaces and intheir interiors, which is due to the metamorphism and differentiation ofmaterials associated with the thermal evolution of these bodies. We will study
the planetary formation and various phenomena there using experimental
approaches based on materials science, theoretical simulations, telescopicobservations, and data analysis obtained by spacecraft. Specifically, ourresearch topics include the formation of meteorites and material
differentiation in the Solar System, instrument development and data analysis
for spacecraft exploration, material dynamics on the surface and the interiorof planets, and high-temperature and high-pressure material science in theEarth and planetary interiors.

Graduate School of Science
2023-2024

Department of Earth a n d Space Science

DepartmentofEarth andSpace Science

Infrared Astronomy Group
Members

Takahiro SUMI (Professor), Kento MASUDA (Assistant Professor)
Daisuke SUZUKI (Assistant Professor)

Home Page

http://www-ir.ess.sci.osaka-u.ac.jp/index_e.html[Research Area]
1) Observational study of Exoplanets
2) Astrobiology3) Observation of gravitational wave events
4) Galactic structure and dark matter

We study various astrophysical phenomena by using ground and spacetelescopes in infrared and develop related instruments. Especially, we focus
on the formation of exoplanets and aim to find a bio-signature in exoplanets
in future. We also conduct optical follow-up observations of gravitational
wave events, studies of the Galactic structure, and dark matter.
We search for exoplanets by using the 1.8m MOA-II telescope with thegravitational microlensing technique. We also construct the 1.8m PRIME
telescope in South Africa to conduct a microlensing exoplanet search ininfrared to find Earth-mass exoplanets. We are planning to join to NASA’s
Roman mission to carry out a microlensing exoplanet survey from space.
We are also studying the observational plan to detect the biosignature in
exoplanets for future space missions.

DepartmentofEarth andSpace Science

Theoretical Condensed-Matter Physics GroupMembers
Home Page

Takahiro HATANO (Professor),
Satoshi YUKAWA(Associate Professor), Kazushi AOYAMA(Assistant Professor),
Tomohiro TANOGAMI (Assistant Professor)
http://noneq.ess.sci.osaka-u.ac.jp/[Research Area]

1) Physics of friction, fracture, and earthquakes:
Dynamics and statistics of fracture process andtheir potential application for earthquake forecast.
Mechanical instability across the scales.
Developing new theoretical tools for time series
analyses of earthquakes.
2) Dynamics of nonequilibrium phenomena inearth and planetary sciences: Heat conduction, spin
flux, granular flow, etc. Phenomena where fluxes,
diffusion, and phase transitions are interrelated.
Such phenomena are investigated from theviewpoint of nonequilibrium statistical mechanics.
3) Statistical physics of frustrated spin systems:
Ordering and defects in pyrochlore and triangularlattices.
4) Information thermodynamics and its application
to fluid mechanics and turbulence

We study dynamics, statistics, and their universality
in various natural phenomena on the Earth andplanets as well as in condensed matter, brazing a
new trail in “cooperative phenomena in many-bodysystems”. Our approaches are based on statisticalmechanics (either equilibrium or nonequilibrium),
nonlinear dynamics, stochastic processes, andcomputational physics.

Graduate School of Science
2023-2024

Department of Earth a n d Space Science

DepartmentofEarth andSpace Science

High-pressure Material Physics Group
Members

Tadashi KONDO (Professor), Masayuki NISHI (Associate Professor),
Tatsuhiro SAKAIYA(Assistant Professor)

Home Page

http://anvil.ess.sci.osaka-u.ac.jp/intro/English/index.html[Research Area]
1) Phase transition and mineral physics in the mantle.
2) Formation, light elements, physical properties of the core.
3) Early Earth & planets, satellite and their evolution.
4) In-situ observation under High P-T condition.
5) Development of High P-T generation & measuring.
Our research interests are in the change of materials underultra-highpressure
andhigh/low
temperaturecorresponding to the planetary interiors. Most materials
change their physical and chemical properties drastically insuch extreme conditions. For example, crystal structure,density, elastic properties, electrical and magneticproperties, bonding nature and chemical reaction withcoexisting phase are important clues for the geophysicalmodeling and understanding the evolution of the planets.
We generate various P-T fields in the laboratory by using
various techniques of high-pressure generation (both staticand dynamic), with various in-situ observations andrecovery analysis. Through these laboratory-based
experiments, we aim to understand comprehensively
planetary system and components from the point of view ofmaterial science.

DepartmentofEarth andSpace Science

Interesting issues in the present Earth and early Earth

Soft Matter Earth & Planetary Science Group
Members Hiroaki KATSURAGI (Professor), Osamu HISATOMI (Associate Professor),

Makoto KATSURA (Assistant Professor), Ken YAMAMOTO (Assistant Professor)

Home Page

http://life.ess.sci.osaka-u.ac.jp/[Research Area]
1) Physics of granular matter and its geophysical application (impact, fracturing, pattern formation etc.)
2) Biophysics
3) Measurement methods for soft matter characterization and environmental study4) Physics of fluids and multiphase systems and its application to nature
Various complex phenomena occurring on thesurface of the Earth and planetary bodies result
from the complicatedcombinations of material

behaviors such as fluidization, solidification, andself organization. We are striving to reveal thefundamental processes governing these naturalcomplex phenomena. Examples include, planetary
surface terrain, origin of life, and fluid-related
phenomena Development of the measurement
techniques and experimental apparatus for various
soft materials is also investigated in this group.

Graduate School of Science
2023-2024

Department of Earth and SpaceScience

DepartmentofEarth andSpace Science

Laser Astrophysics Group（Institute of Laser Engineering）

Members

Youichi SAKAWA (Associate Professor), Takayoshi SANO (Associate Professor),
Hironori MATSUMOTO (Concurrent Professor)

Home Page

https://www.ile.osaka-u.ac.jp/research/lap/home_e.html[Research Area]
1) Collisionless shock and cosmic ray acceleration
2) Magnetic reconnection and astrophysical transient phenomena
3) Plasma instability and turbulence driving mechanism
Using high-energy and high-intensity lasers in Japan and abroad, wewill realize high-energy-density states and ultrafast plasma flows in thelaboratory that would exist only in the universe, and we understand thenature of astrophysical plasmas. By using high-intensity picosecondand femtosecond lasers, in addition to high-energy nanosecond lasers,
we will study such as relativistic wave-particle interactions andrelativistic plasma generation. In addition to laser experiments,
magneto-hydrodynamic and plasma-particle simulations will be
performed to understand the physical mechanisms from theoretical andexperimental perspectives.

High-power laser systems at ILE,
Osaka University (GXII & LFEX)

Graduate School of Science
2023-2024