Lunar Dusty Plasma Environmentand Transport Processes

Contents• Lunar Dusty Plasma Environment

– Theoritical Models

– Apollo Observations

– Surveyor Results

– Clementine Results

– Selene Results

– LRO Results

– Simulations

• Observations – Open Problems

– Radio Mapping of Lunar Dusty Plasma Environment

– In-Situ Studies

The Lunar Dusty Plasma EnvironmentTheoritical Model

• Solar Wind Flux on Lunar Surface : 1.7 × 1025 p+ s-1

– Equivalent to 27 gram (!) s-1 [1]

– Flux of solar wind ions lower when in the magnetotail of Earth (~3 days before full moon to ~3 days after) [2]

Credit: http://www.nasa.gov/topics/moonmars/features/magnetotail_080416.html

The Lunar Dusty Plasma EnvironmentTheoritical Model

• Earths Magnetotail on Lunar Surface : – Several hundreds of Volt of Surface

potential in the Day side, and negative several hudred Volt in the nightside [3]

Credit: http://www.nasa.gov/topics/moonmars/features/magnetotail_080416.html

The Lunar Dusty Plasma EnvironmentTheoritical Model

Lunar Dusty Plasma Environment Structure. Credits: Left : ESA, Right : UCLA

The Lunar Dusty Plasma EnvironmentTheoritical Model

Lunar Dusty Plasma Environment Structure. Credits: T.J. Stubbs, UMBC

The Lunar Dusty Plasma EnvironmentTheoritical Model

Lunar Dusty Plasma Environment Structure. Credits: T.J. Stubbs, UMBC

Processes :1) Earth's Magnetotail charges the Lunar Dayside Negatively, which is discharged by Solar Wind, but Nightside Charge remains2) Solar Wind, outside the Magnetopause, charges the Dayside positively.3) Dust Is charged and lifted above lunar surface, like a fluid layer.4) Waves are seen in this Layer5) Dust is transported accross the Layer

The Lunar Dusty Plasma EnvironmentApollo Results

Dust fountain as seen by Apollo 17 Commander E. Cernan. Credits: T.J. Stubbs, UMBC

The Lunar Dusty Plasma EnvironmentSurveyor Results

Dust Floating in the Horizon, after: T.J. Stubbs, UMBC

The Lunar Dusty Plasma EnvironmentClementine Results

Dust Glowing near the Horizon, as seen by Clementine Star Tracker Camera, after: T.J. Stubbs, UMBC

The Lunar Dusty Plasma EnvironmentSelene Results

Energy Flux, as measured by the two sensors ESA-1 and IEA on Selene Spacecraft [3] NOTE: Unit Problems

The Lunar Dusty Plasma EnvironmentLRO Results

Hydrogen Atom Count, from LRO Data, Possibly related to Solar Wind charging of Regolith [4]

The Lunar Dusty Plasma EnvironmentObservation – Open Problems

1.Continuous observation of the Lunar Dusty Plasma Environment

1. Determine the charge, the size and velocity distribution of levitated/transported lunar dust function of local time, and position along the lunar orbit.2. Measure the variations of the charge density distribution on the surface, and the plasma properties of the near-surface environment.3. Map the variable structure of the near-surface electric field.4. With narrow beam, investigate the properties of Dayside and Nightside Plasma Environemnt, and quantify the Transport.5. Investigate the Plasma near Craters and Rillies

Radio Observations

The Lunar Dusty Plasma EnvironmentObservation – Open Problems

1.The LADEE Spacecraft has performed some In-situ Studies2.Future Lunar Landers, including GLXP Landers can take part in such studies.

In-Situ Studies

Bibliography1) SOLAR WIND FLUENCE TO THE LUNAR SURFACE, D. M. Hurley, W. M. Farrell, 44th Lunar

and Planetary Science Conference (2013)

2) Nasa Science News http://science.nasa.gov/science-news/science-at-nasa/2008/17apr_magnetotail/ (No Publication to the best of my knowledge)

3) NIGHT SIDE LUNAR SURFACE POTENTIAL IN THE EARTH’S MAGNETOSPHERE. Y. Saitoa, M.N. Nishinoa, S. Yokotaa, H. Tsunakawab, M. Matsushimab, F. Takahashib, H. Shibuyac, H. Shimizud, Advances in Space Research, 2013, Elsevier

4) Lunar Dusty Plasma Environment, S.I. Popel et al, Presentation, The Third Moscow Solar System Symposium