About us

This post is also available in: Japanese

About Us

We are investigating solar-planetary and upper-atmosphere phenomena based on ground-based remote-sensing data, spacecraft data, modeling and computer simulations as well as developments of optical-infrared and radio instruments for space missions and ground experiments. We have observatories at five stations in Japan, and at Haleakala. In addition, we are carrying out world-wide observations at Mauna-Kea/Hawaii, Alaska, Scandinavia, etc. In cooperation with JAXA, our optical and radio instruments have been installed on space missions such as, Kaguya, Reimei and Akebono. Recently our research field has extended to atmosphere on exoplanets.

Recent Research Subjects


  • Solar radio emissions and particle acceleration with IPRT/AMATERAS
  • Multi-wavelength observation of solar active region

Planets, and Satellites


  • Io-originated teneous gas and plasmas in the Jupiter’s inner magnetosphere observed with HISAKI, and the Haleakala telescopes
  • Jupiter’s infrared aurora taken with Subaru/IRCS and NASA/IRTF/CSHELL/ISHELL
  • Jupiter’s synchrotron radio emission measured with IPRT/AMATERAS
  • Jupiter’s decametric radio emission observed with the HF antennas
  • Jupiter’s magnetospheric dynamics derived by Galileo


  • Satrun’s auroral kilometric radio emission based on the Cassini data
  • Enceladus’ oxygen torus obtained with Haleakala/T60/Vispec

Venus and Mars

  • Venus’ middle and upper atmosphere derived by Akatsuki/IR1 and IR2
  • Venus’ mesospheric wind and temperature field based on MILAHI data
  • Minor tracer gases on Mars revealed by MEX/PFS, and Exomars/TGO and ground-based telescopes(Subaru, SOFIA, ALMA etc)
  • Martian atmospheric gravity waves observed by MEVEN
  • Periodic variations of Venus upper atmosphere by Hisaki


Auroral Ionosphere, and Magnetosphere

  • Small-scale discrete aurora and pulsating aurora obtained with Reimei, ground-based imagers (Poker Flat/MIRACLE/ALIS) and EISCAT/ESR
  • Auroral polarization observed at Pokar Flat/Alaska
  • Auroral radio emissions measured with ground, rocket and space experiments
  • High-latitude ionospheric outflow and upflow obtained with Akebono and ground-based spectrometer at Svalvard
  • Radiation belt high-energy particle revealed with ERG and ground-based LF radar
  • Polar cap auroral dynamics in the northward IMF conditions
  • Evolution of convection electric field and energy transfer in the magnetosphere during geomagnetically disturbed conditions

Upper and middle atmosphere

  • Concentric atomospheric gravity waves at mid- and low-latitudes thermosphere observed by ISS/IMAP-VISI
  • Tenuous gas analysis in the upper atmosphere
  • Stratospheric sudden temperature increase


  • Moon’s surface structure and plasma environment observed with Kaguya


  • Polarization observation of exoplanetary atmosphere with T60/DiPOL2

    Modeling and Simulation

Modeling and Simulation

  • Numerical simulation of molecular clouds in protoplanetary disk
  • KH instability in the Martian ionosphere and Mercury magnetosphere
  • Generation and loss processes of Venus’ sulfuric acid clouds with a GCM model
  • Full-particle model of the Martian upper theremosphere-exosphere (Direct Simulation Monte Carlo (DSMC) method)
  • Atmospheric escape from Mars and Venus
  • Development of Martian GCM model
  • Dynamics of Joupiter’s inner magnetosphere
  • Jupiter stratospheric GCM model
  • Martian ancient atmosphere derived by a GCM model


Space-borne Instruments

  • Reimei/MAC (Multi-spectral auroral camera)
  • ISS/IMAP-VISI (Visible and near-Infrared Spectrograph Instrument)
  • ERG/PWI (Plasma wave)
  • BepiColombo/MMO(Mercury Magnetospheric Orbiter)/PWI(Plasma Wave Investigation)
  • JUICE/RPWI(Plasma wave) and SWI(Submillimeter Wave Instrument)
  • Mars Moon eXploration/NIRS4 (Near-infrared hyper-spectral imager)
  • Gaussian baffle vane for future Mars mission

Ground-based instruments

Overview of our laboratories


This post is also available in: Japanese