On vertical electric fields at lunar magnetic anomalies

Järvinen, R.; Alho, Markku; Kallio, Esa; Würz, Peter; Barabash, S.; Futaana, Yoshifumi

doi:10.1002/2014gl059788

Cited by 40 publications

(57 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Generally, these models, consistent with observations, have shown that strong magnetic anomalies may shield the lunar surface from solar wind and have a direct impact on surface weathering and swirl albedo markings [ Blewett et al , ; Poppe et al , ]. Recently, Jarvinen et al [] using a three‐dimensional hybrid model studied the interaction between a single magnetic dipole mimicking the Gerasimovich magnetic anomaly. Their studies, consistent with Chandrayaan‐1 ENA observations, estimated an electrostatic potential of <+300 V above the magnetic anomalies.…”

Section: Introductionmentioning

confidence: 76%

“…Apart from observations, several attempts have been made to model the solar wind plasma interaction with lunar magnetic anomalies theoretically, numerically, and experimentally using single dipole [ Siscoe and Goldstein , ; Harnett and Winglee , , ; Poppe et al , ; Kallio et al , ; Wang et al , , ; Shaikhislamov et al , ; Jarvinen et al , ; Deca et al , ; Ashida et al , ] and multidipole [ Harnett and Winglee , ] approximations. Generally, these models, consistent with observations, have shown that strong magnetic anomalies may shield the lunar surface from solar wind and have a direct impact on surface weathering and swirl albedo markings [ Blewett et al , ; Poppe et al , ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Solar wind plasma interaction with Gerasimovich lunar magnetic anomaly

et al. 2015

View full text Add to dashboard Cite

We present the results of the first local hybrid simulations (particle ions and fluid electrons) for the solar wind plasma interaction with realistic lunar crustal fields. We use a three‐dimensional hybrid model of plasma and an empirical model of the Gerasimovich magnetic anomaly based on Lunar Prospector observations. We examine the effects of low and high solar wind dynamic pressures on this interaction when the Gerasimovich magnetic anomaly is located at nearly 20∘ solar zenith angle. We find that for low solar wind dynamic pressure, the crustal fields mostly deflect the solar wind plasma, form a plasma void at very close distances to the Moon (below 20 km above the surface), and reflect nearly 5% of the solar wind in charged form. In contrast, during high solar wind dynamic pressure, the crustal fields are more compressed, the solar wind is less deflected, and the lunar surface is less shielded from impinging solar wind flux, but the solar wind ion reflection is more locally intensified (up to 25%) compared to low dynamic pressures. The difference is associated with an electrostatic potential that forms over the Gerasimovich magnetic anomaly as well as the effects of solar wind plasma on the crustal fields during low and high dynamic pressures. Finally, we show that an antimoonward Hall electric field is the dominant electric field for ∼3 km altitude and higher, and an ambipolar electric field has a noticeable contribution to the electric field at close distances (<3 km) to the Moon.

show abstract

Section: Introductionmentioning

confidence: 76%

Section: Introductionmentioning

confidence: 99%

Solar wind plasma interaction with Gerasimovich lunar magnetic anomaly

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The computational investigation into mini-magnetospheres has become an area of considerable interest. A number of papers on hybrid (Bamford et al 2008;Gargaté et al 2008;Kallio et al 2012;Poppe et al 2012) and particle-in-cell (PIC) (Kallio et al 2012;Bamford et al 2013aBamford et al , 2013bBamford et al , 2015Deca et al 2014Deca et al , 2015Jarvinen et al 2014;Cruz et al 2015Cruz et al , 2016Dyadechkin et al 2015;Fatemi et al 2015) simulations have been authored, following from previous magnetohydrodynamic (MHD) simulations (Harnett & Winglee 2002Kurata et al 2005). Here we perform fully self-consistent PIC simulations in 2D and 3D, with a realistic proton-to-electron mass ratio.…”

Section: Introductionmentioning

confidence: 99%

3d Pic Simulations of Collisionless Shocks at Lunar Magnetic Anomalies and Their Role in Forming Lunar Swirls

Bamford

Alves

Cruz

et al. 2016

ApJ

View full text Add to dashboard Cite

Investigation of the lunar crustal magnetic anomalies offers a comprehensive long-term data set of observations of small-scale magnetic fields and their interaction with the solar wind. In this paper a review of the observations of lunar mini-magnetospheres is compared quantifiably with theoretical kinetic-scale plasma physics and 3D particlein-cell simulations. The aim of this paper is to provide a complete picture of all the aspects of the phenomena and to show how the observations from all the different and international missions interrelate. The analysis shows that the simulations are consistent with the formation of miniature (smaller than the ion Larmor orbit) collisionless shocks and miniature magnetospheric cavities, which has not been demonstrated previously. The simulations reproduce the finesse and form of the differential proton patterns that are believed to be responsible for the creation of both the "lunar swirls" and "dark lanes." Using a mature plasma physics code like OSIRIS allows us, for the first time, to make a side-by-side comparison between model and space observations. This is shown for all of the key plasma parameters observed to date by spacecraft, including the spectral imaging data of the lunar swirls. The analysis of miniature magnetic structures offers insight into multi-scale mechanisms and kinetic-scale aspects of planetary magnetospheres.

show abstract

“…Some numerical simulations using a particle model have focused on this phenomenon. [8][9][10] We have another interesting example, this one from space engineering, of the interaction of plasma flow with a smallscale magnetic dipole. The magnetic sail 11 and the magnetoplasma sail (MPS) 12 have been proposed as possible systems for interplanetary flight.…”

Section: Introductionmentioning

confidence: 99%

Full kinetic simulations of plasma flow interactions with meso- and microscale magnetic dipoles

et al. 2014

View full text Add to dashboard Cite

We examined the plasma flow response to meso-and microscale magnetic dipoles by performing three-dimensional full particle-in-cell simulations. We particularly focused on the formation of a magnetosphere and its dependence on the intensity of the magnetic moment. The size of a magnetic dipole immersed in a plasma flow can be characterized by a distance L from the dipole center to the position where the pressure of the local magnetic field becomes equal to the dynamic pressure of the plasma flow under the magnetohydrodynamics (MHD) approximation. In this study, we are interested in a magnetic dipole whose L is smaller than the Larmor radius of ions r iL calculated with the unperturbed dipole field at the distance L from the center. In the simulation results, we confirmed the clear formation of a magnetosphere consisting of a magnetopause and a tail region in the density profile, although the spatial scale is much smaller than the MHD scale. One of the important findings in this study is that the spatial profiles of the plasma density as well as the current flows are remarkably affected by the finite Larmor radius effect of the plasma flow, which is different from the Earth's magnetosphere. The magnetopause found in the upstream region is located at a position much closer to the dipole center than L. In the equatorial plane, we also found an asymmetric density profile with respect to the plasma flow direction, which is caused by plasma gyration in the dipole field region. The ion current layers are created in the inner region of the dipole field, and the electron current also flows in the region beyond the ion current layer because ions with a large inertia can closely approach the dipole center. Unlike the ring current structure of the Earth's magnetosphere, the current layers in the microscale dipole fields are not circularly closed around the dipole center. Since the major current is caused by the particle gyrations, the current is independently determined to be in the direction of the electron and ion gyrations, which are the same in both the upstream and downstream regions. The present analysis on the formation of a magnetosphere in the regime of a microscale magnetic dipole is significant for understanding the solar wind response to the crustal magnetic anomalies on the Moon surface, such as were recently observed by spacecraft. V C 2014 AIP Publishing LLC. [http://dx.

show abstract

On vertical electric fields at lunar magnetic anomalies

Cited by 40 publications

References 14 publications

Solar wind plasma interaction with Gerasimovich lunar magnetic anomaly

Solar wind plasma interaction with Gerasimovich lunar magnetic anomaly

3d Pic Simulations of Collisionless Shocks at Lunar Magnetic Anomalies and Their Role in Forming Lunar Swirls

Full kinetic simulations of plasma flow interactions with meso- and microscale magnetic dipoles

Contact Info

Product

Resources

About