賴淑華 博士 (Dr. Shu-Hua Lai)
國立中央大學太空科學與科技研究中心 (CAPE, NCU)
September 18, 2026 (Friday), 15:00
S4-917, Chien-Shiung Building
 

研究緣起
太陽系裡最靠近太陽的行星是水星，但人類對水星的探測次數遠少於火星。我們一直非常關心極端強烈太空天氣對地球磁層的影響，但地球面臨的真正「世紀級」極端事件（如卡靈頓等級）往往百年僅得一見，使我們很難從中拼湊出完整共通的物理機制。幸好，太陽系裡有一顆同樣具有全尺度磁層結構的類地行星—水星，幾乎經常性地面臨對地球而言屬於浩劫等級的太陽風衝擊! 水星磁層因而成為研究極端太空天氣與磁層耦合的天然實驗室，其物理機制可直接類推至極端條件下的地球。也因為如此，即將在今年底正式進入繞軌任務階段的BepiColombo — 歐洲與日本太空機構聯合執行的旗艦型水星探測任務 — 正是讓我們能把這座天然實驗室看個明白、與國際酬載團隊及科學團隊一起檢驗這些極端機制的絕佳機會。

Abstract
Mercury serves as an ideal natural laboratory for studying planetary responses to extreme space weather, offering key insights applicable to Earth. In anticipation of BepiColombo's upcoming orbital mission, I synthesize a scientific roadmap based on my four closely connected studies of Mercury's space environment. Using in situ data from Helios and Parker Solar Probe, we first establish criteria to categorize an extreme solar-wind regime characterized by an extremely low fast-mode Mach number within depleted compound structures. Under this extremely-low-Mach-number regime, planetary bow shocks substantially weaken or vanish entirely, directly exposing Mercury's magnetosphere to the solar wind. At the magnetopause, by analyzing MESSENGER boundary-crossing data to reconstruct KHI waveforms and normal vectors, we identify sunward-steepening directions opposite those of ordinary trailing KHI vortices, providing critical observational evidence for KHI-driven fast-mode shocks. Finally, quantifying the associated energy and momentum fluxes reveals that this fast-mode-wave-driven transport efficiently carries substantial energy directly into the cross-tail current sheet. Rather than relying solely on dayside magnetic reconnection, this KHI mechanism provides an alternative energy-loading pathway that can trigger geomagnetic storm activity across planetary magnetospheres. As a member of the BepiColombo science team, I will have the opportunity to collaborate with international instrument and science teams from Japan (JAXA) and Europe (ESA) to investigate these critical questions.