Program uses Singapore Time and is 8 hours ahead of GMT

PS Kamide Lecture/Live Q&A Mon-01 Aug 16:30 – 17:15

Circulation and Escape of Planetary Ions at Mercury

Mercury, the closest planet to the Sun, is the telluric planet in the Solar System that has been less visited by spacecraft. Previous observations have revealed that Mercury has a weak intrinsic magnetic field. The interaction of this weak planetary magnetic field with a strong solar wind gives birth to a magnetosphere that is relatively small in size but particularly dynamic compared to that of Earth. The incident solar wind plasma interacts with the tenuous neutral atmosphere, and also with the surface of the planet directly resulting in producing planetary ions. Thus, the plasma in the magnetosphere consists not only of solar wind plasmas but also of planetary ions. The motion of these charged particles is governed by the ambient magnetic/electric field in the magnetosphere. During their convective motion, charged particles either undergo acceleration and energization, or escape from the magnetosphere into the interplanetary medium, or fall back to the surface of Mercury. Plasma sputtering onto the surface may result in long-term space weather at Mercury. Using the global hybrid simulation, the circulation and escape of planetary ions at Mercury, and penetration of solar wind plasmas have been investigated. In particular, the different trend between sodium ions and protons of planetary origin is found and will be discussed in this talk.

Dr. Sae Aizawa is a postdoctoral researcher at ISAS/JAXA in Japan and Pisa University in Italy with a fellowship from JSPS (the Japan Society for the Promotion of Science). She received her Ph.D. in the double degree program from both the Graduate School of Science at Tohoku University in Japan and Sorbonne University in France in 2019, and worked as a postdoctoral researcher at IRAP (Institut de Recherche en Astrophysique et Planetologie) in France before joining ISAS and Pisa University in April 2022.

Her main research interest is to understand the plasma physics and the role of planetary plasmas in Mercury’s magnetosphere, and coupling with exosphere and its surface. She has been working on several scientific questions using both in-situ data and numerical simulations. Recently, she has worked as a Co-Investigator of Mercury Electron Analyzer onboard Mio/BepiColombo and also as Co-Principal Investigator of ISSI international team.