[P-PS02] Lunar Science and Exploration

[PPS02-P01] Observations and Simulations of Lunar Ion Dynamics in Earth’s Magnetotail Lobes

*Khan-Hyuk Kim¹, Jaehee Lee¹, Yewon Hong¹, Dongseok Yun¹, Ho Jin¹, Seul-Min Baek² (1.School of Space Research, Kyung Hee University, Korea, 2.Korea Astronomy and Space Science Institute, Daejeon, Republic of Korea)

Keywords:

Lunar ions,Earth’s magnetotail lobes,Kaguya observations,Test-particle simulations

We analyzed 1.5 years of Kaguya observations (January 2008–June 2009) to characterize lunar-origin ions within Earth’s magnetotail lobes. These ions were detected on the dayside with energies of 50–1000 eV at altitudes of 30–120 km. To investigate their origin and dynamics, we performed test-particle simulations of cold ions (a few eV or less) generated at the lunar surface and in the exosphere. The results indicate that the Procellarum KREEP Terrane is the primary source region of lunar-origin ions observed at spacecraft altitudes. The simulations further show that ions originating in the exosphere are more effectively energized than surface-generated ions. However, the ion energization obtained in simulations with typical lunar surface potential and lobe convection velocity is lower than that of lunar-origin ions observed at spacecraft altitudes, suggesting that additional acceleration mechanisms are required to explain the observations.