Development of the instrument onboard the spacecraft

Credit by NASA

Credit by NASA

Staffs work for long-term, which do not always provide products soon. Now, we are running following projects, in which we take the responsibility for electric / radio / digital integratation instruments.
– Small-sized EUV explorer ‘Exceed’ (Launch: 2013?)
– Mercury mission ‘BepiColombo’ (Launch: 2014)
– Small-sized radiation belt explorer ‘ERG’ (Launch: 2014)
We also join the base investigations of the multi-spacecraft magnetospheric ‘SCOPE’, future Mars, and future Jupiter missions, which will be in the end of next decade. Let’s enjoy with the short-term ‘ground-based and orbiter observations’, ‘numerical studies’, and ‘base development of og sensor technologies’.

Magnetic and ionospheric electric fields

magnetosphere

The Earth has the region dominated by its magnetic field, called magnetosphere. In the magnetosphere, large-scale magnetic disturbance phenomena such as storms and substorms are observed by the input of energy from solar wind. These phenomena are triggered by convection electric fields that cause the transport and acceleration of charged particles and electromagnetic energies in the magnetosphere. Therefore, investigating evolution of convection electric fields is essential to understand the energy transport associated with solar wind disturbance in the magnetosphere-ionosphere coupled system. Currently, we are trying to clarify evolution of convection electric fields and the energy transport associated with magnetic disturbance phenomena by the in-situ multiple observations of magnetic and ionospheric electric fields – using by THEMIS, RBSP, SuperDARN, and etc.

金星大気流出

Credit by ESA

Credit by ESA

金星は地球のような固有磁場をもたず、超高層大気が太陽風とよばれる太陽から吹き付けるプラズマや磁場の流れと直接相互作用しています。この直接の相互作用により、金星超高層の電離大気は太陽風中の電磁場によって加速を受け、宇宙空間へ流出するという現象が起こっています。 この大気流出現象は金星の大気進化に大きな影響を及ぼしてきたと考えらており、過去の金星の姿を突き止めるため現在も世界中で研究が行われています。我々は欧州の探査機Venus Expressが観測したデータを用い、金星の電離大気がどのような物理過程で加速され、宇宙空間へ流出していっているのかを調べています。

Due to lack of intrinsic magnetic field on Venus, the upper atmosphere is directly interacted with the solar wind. As a result of the interaction, ionospheric ions can be accelerated beyond an escape velocity and removed from Venus. The fact has played an important role for the atmospheric evolution on Venus. Collaborating with European Institute, we analyze the data from Venus Express to study about the ion escape from Venus. Purpose of this study is to figure out physical processes of the ion acceleration and to determine a total amount of removed ionospheric components with a dependence on the solar wind’s conditions.