Mercury
Mercury has a tenuous atmosphere containing alkali metals. In particular, the neutral sodium emission is bright and suitable for ground-based observation.
We use Tohoku University’s 60 cm telescope (T60) in Hawaii to perform 2D observations of Mercury’s exosphere.
In coordination with the BepiColombo spacecraft, which will enter Mercury’s orbit in 2027, we aim to observe Mercury both from the ground and in situ. Mercury’s magnetosphere is much smaller than Earth’s and varies on a timescale of just a few minutes.
By observing these rapid variations, we hope to better understand the interaction between Mercury’s atmosphere and its magnetic environment.
“Mio” is a Mercury exploration spacecraft developed jointly by Japan (JAXA) and Europe (ESA) as part of the BepiColombo mission, launched in 2018. Its purpose is to investigate Mercury, the planet closest to the Sun. Mio is designed to study Mercury’s magnetic field, magnetosphere, and interaction with the solar wind in detail. Due to its proximity to the Sun, MIO will conduct observations in a hot and harsh environment. It is hoped that elucidating Mercury’s environment and origin will provide clues to understanding the origins of the solar system.
Tohoku University is involved in the development of the Plasma Wave Investigation (PWI) and the Mercury Sodium Atmosphere Spectral Imager (MSASI). Image by JAXA
ISAS Mio project page
