Interaction between terrestrial plasma sheet electrons and the lunar surface: Kaguya (SELENE) observations

Details Interaction between terrestrial plasma sheet electrons and the lunar surface: Kaguya (SELENE) observations Interaction between terrestrial plasma sheet electrons and the lunar surface: Kaguya (SELENE) observations

Dec 2009

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009agufm.p23c1258h&link_type=abstract

American Geophysical Union, Fall Meeting 2009, abstract #P23C-1258

Physics

[2764] Magnetospheric Physics / Plasma Sheet, [5421] Planetary Sciences: Solid Surface Planets / Interactions With Particles And Fields, [6250] Planetary Sciences: Solar System Objects / Moon

Scientific paper

The moon stays in the Earth’s magnetosphere for several days around the full moon period. The plasma in the magnetosphere has different properties from the solar wind such as in density or energy, and interacts with the lunar surface. We found an interesting phenomenon concerning the lunar plasma environment when the moon is in the magnetosphere through the analysis of the data obtained by MAP-PACE and MAP-LMAG onboard Kaguya (SELENE). Most electrons in the magnetosphere gyrate around the magnetic field line with smaller Larmor radius than Kaguya's orbital height (nominally: 20-100 km). However, some of the electrons in the central plasma sheet have the Larmor radii greater than or equal to Kaguya's orbital height (1 keV electron has about 100 km Larmor radius in the 1 nT magnetic field). When the magnetic field is parallel to the lunar surface, these relatively high-energy electrons hit the lunar surface and are absorbed. This can be observed as an empty region in the electron distribution function, which is originally isotropic in the terrestrial plasma sheet. We have examined the data obtained by Kaguya and found characteristic electron distributions as we expected. However, we also found that the empty region in the observed phase space tends to be smaller than a theoretically derived forbidden region. One of the possible reasons for this is the presence of the electric field perpendicular to the magnetic field, and we can fit the forbidden region with the observed one if we assume the perpendicular electric field of 10 mV/m. Another possible reason is that the plasma is diffused in the phase space to make the empty region smaller by unstable waves. Although those reasons should be examined carefully, the partial loss in the distribution function due to the absorption of gyrating particles by lunar surface may be a general phenomenon when plasma and a solid surface interact.

Affiliated with

Also associated with

No associations

Rating

Interaction between terrestrial plasma sheet electrons and the lunar surface: Kaguya (SELENE) observations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Interaction between terrestrial plasma sheet electrons and the lunar surface: Kaguya (SELENE) observations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interaction between terrestrial plasma sheet electrons and the lunar surface: Kaguya (SELENE) observations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1769539