scholarly journals 2.2.5 Electrostatic Disruption of Lunar Dust Particles

1976 ◽  
Vol 31 ◽  
pp. 238-240 ◽  
Author(s):  
John W. Rhee

An investigation has been made to study a possibility that dust particles might catastrophically explode on the lunar surface due to electrostatic charging. It is shown that for the dark side along the terminator zone, dust balls and compact stony particles of micron and submicron sizes will be blown up if their surface potential is as low as a kilovolt negative. This mechanism will not operate on the sunlit side because the potential is only 3.5 ~ 20 volts positive. Some of these fragments may possibly levitate in the vicinity of the terminator.

2013 ◽  
Vol 79 (4) ◽  
pp. 405-411 ◽  
Author(s):  
SERGEY I. POPEL ◽  
LEV M. ZELENYI

AbstractFrom the Apollo era of exploration, it was discovered that sunlight was scattered at the terminators giving rise to “horizon glow” and “streamers” above the lunar surface. Subsequent investigations have shown that the sunlight was most likely scattered by electrostatically charged dust grains originating from the surface. A renaissance is being observed currently in investigations of the Moon. The Luna-Glob and Luna-Resource missions (the latter jointly with India) are being prepared in Russia. Some of these missions will include investigations of lunar dust. Here we discuss the future experimental investigations of lunar dust within the missions of Luna-Glob and Luna-Resource. We consider the dusty plasma system over the lunar surface and determine the maximum height of dust rise. We describe mechanisms of formation of the dusty plasma system over the Moon and its main properties, determine distributions of electrons and dust over the lunar surface, and show a possibility of rising dust particles over the surface of the illuminated part of the Moon in the entire range of lunar latitudes. Finally, we discuss the effect of condensation of micrometeoriod substance during the expansion of the impact plume and show that this effect is important from the viewpoint of explanation of dust particle rise to high altitudes in addition to the dusty plasma effects.


2018 ◽  
Vol 7 (2.24) ◽  
pp. 69
Author(s):  
Arunima Prakash ◽  
Diwakar R. Marur ◽  
Sakshi Namdeo

Moon, our closest celestial neighbor and Earth’s only natural satellite is of utmost scientific importance. So far there have been 67 missions to the Moon, thus to enhance and aid further research understanding of lunar surface is vital. The Moon meets the Earth’s magnetotail (an extension of Earth’s magnetosphere) twice in a month encountering a gigantic sheet of ionized particles or plasma. These charged particles intersperse on the lunar dust and give it a negative charge. The electric field created by this phenomenon creates a substantial potential difference across the two sides of the lunar surface. Electrified dust grains can adhere to machinery and the large electric fields can affect electronics of landers or payload machinery. A payload is proposed Lunar Electric Surface Potential Analyzer (LESPA) to measure the effects of these magnetotail crossings. LESPA will need to establish a low BER link with the in-orbit lunar satellite at optimum frequencies to relay the raw data. This paper aims to analyze and study the link budget requirements for designing an Independent Communication Module (ICM) for LESPA as well as antenna models for the transmitter. The scope of the designed ICM is to ultimately assist in designing lander missions for future lunar exploration and aid in future lunar exploration missions and colonization activities. 


Author(s):  
Alexander V. Zakharov

The surface of the Moon, as well as the surface of an airless body of the solar system, is subject to constant bombardment of micrometeorites, the effects of solar radiation, solar wind, and other space factors. As a result of the impact of high-speed micrometeorites for billions of years, the silicate base of the lunar surface is crushed, turning into particles with an approximately power-law-sized distribution. Given the explosive nature of the occurrence, these particles are characterized by an extremely irregular shape with pointed edges, either droplets close to spheres or conglomerates sintered at high temperatures. The plasma of the solar wind and the solar radiation, especially its ultraviolet part of the spectrum, when interacting with the upper layer of regolith causes a charge of the regolith upper layer and creates a near-surface double layer and an electric field. In this field, regolith particles of micron and submicron sizes can break away from the surface and levitate above the surface. Such dynamic processes lead to the transfer of dust particles over the surface of the Moon, as well as to the scattering of sunlight on these particles. Glows above the lunar surface of this nature were observed by television systems of American and Soviet landers in the early stages of lunar exploration. The American astronauts who landed on the lunar surface during the Apollo program experienced the aggressive properties of lunar dust. The results of the Apollo missions showed that dust particles are one of the main causes of danger to humans, spacecraft systems, and activities on the lunar surface. Based on the results of late 20th- and early 21st-century lunar research, as well as the proposed models, the article discusses the formation of the lunar regolith and the near-surface exosphere of the Moon under the influence of external factors in outer space. Relevant considerations include the causes and conditions of dust particle dynamics, the consequences of these processes as well as possible threats to humans, engineering systems during the implementation of planned research programs, and the exploration of the Moon. Also of relevance are models of the formation of a plasma-dust exosphere, the dynamics of dust particles in the near-surface region, and dust clouds at a distance of several tens of kilometers from the Moon’s surface, based on the available experimental data. The main unresolved problems associated with the dynamics of the dust component of lunar regolith are given, and methods for solving problematic issues are discussed. The Moon research programs of leading space agencies and their role in the study of Moon dust, its dynamics, human impact, and its activities in the implementation of promising programs for the study and exploration of the Moon are examined.


2011 ◽  
Vol 59 (13) ◽  
pp. 1446-1454 ◽  
Author(s):  
N. Duncan ◽  
Z. Sternovsky ◽  
E. Grün ◽  
S. Auer ◽  
M. Horanyi ◽  
...  

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2466
Author(s):  
Qingwen Rao ◽  
Guanjun Xu ◽  
Wangchen Mao

In this paper, the detection of the lunar surface soil permittivity with megahertz electromagnetic (EM) waves by spaceborne radar is studied based on the EM scattering theory, the Boltzmann–Shukla equations, and the improved scattering matrix method (ISMM). The reflection characteristics of the lunar surface soil subject to megahertz waves are analyzed through the EM scattering theory and expressed by the lunar surface soil permittivity. Then, the lunar ionosphere is assumed to be composed of dusty plasma, and its EM characteristics are described with the Boltzmann–Shukla equations. Finally, the transmission and reflection characteristics of the propagation of EM waves in the lunar ionosphere are numerically calculated with ISMM. Thus, the complex permittivity of lunar surface soil is obtained. In addition, the effects of detection environment situations, such as the lunar illumination intensity, characteristics of the lunar dust and dust charging process in the lunar ionosphere, on the amplitude and phase of EM waves are also investigated in this study. The simulation results show that an EM wave at a high frequency induces a strong effective wave with a stable phase shift and a significantly small interferential wave. Moreover, the lunar illumination is more effective under EM waves in low frequency bands; the characteristics of the lunar dust have a notable influence on the transmission and absorption coefficients of the effective waves. These conclusions help in real applications involving the detection of the lunar surface soil permittivity by spaceborne radar in various lunar environments.


2021 ◽  
Author(s):  
Donald Hendrix

<p>With the Artemis mission set to launch in 2024, returning humans to the lunar surface for the first time in over half a century, it is imperative to ensure human health and safety on a variety of fronts. Lunar dust exposure is one of many areas of concern regarding astronaut health and safety. During the Apollo missions it was reported that lunar dust was a nuisance and induced allergic-like symptoms upon exposure. In addition, it was also reported that instruments became coated with dust that was difficult to remove, and that the dust adhered to everything and tore through space suit fabric. Numerous inhalation studies have determined that lunar dust is more toxic than analogous terrestrial materials but less so than silica dust. Apollo dust mitigation systems were successful on some missions but failed on others. As humans are to stay on the lunar surface for extended periods relative to the Apollo missions, it is vital to fabricate instruments that would address the lunar dust problem with greater reliability. There must be multiple steps to remove all lunar dust, including the ultra-fine <10 µm fraction which was the most difficult dust size to remove. There must be multiple steps regarding lunar dust removal including a chamber to remove dust and de-suit, and a vacuum with high level HEPA filtration to remove dust. The first chamber would be to filter out any dust that comes into the module from the outside. Once all the air is clear, then the next step would be to remove any remaining dust on the suits using a hand-held vacuum with a HEPA H14 filter which only allows up to a maximum 0.005% of particles 100 nm in size to pass through the filter. Then, it would be safe to de-suit. It would be wise to have a second chamber between the first chamber and the command center of the lunar module that would vacuum any remaining dust before opening to the main command chamber. Ultra-high quality HEPA filters of both the chamber and hand-held vacuum systems should be replaced frequently to maintain optimal dust mitigation. Investing time and resources into lunar dust mitigation should be a top priority for the upcoming Artemis mission to avoid the issues encountered on the Apollo missions.</p>


1976 ◽  
Vol 31 ◽  
pp. 233-237 ◽  
Author(s):  
Otto E. Berg ◽  
Henry Wolf ◽  
John Rhee

In December, 1973, a Lunar Ejecta and Meteorites (LEAM) experiment was placed in the Taurus-Littrow area of the moon by the Apollo 17 Astronauts. Objectives of the experiment were centered around measurements of impact parameters of cosmic dust on the lunar surface. During preliminary attempts to analyze the data it became evident that the events registered by the sensors could not be attributed to cosmic dust but could only be identified with the lunar surface and the local sun angle. The nature of these data coupled with post-flight studies of instrument characteristics, have led to a conclusion that the LEAM experiment is responding primarily to a flux of highly charged, slowly moving lunar surface fines. Undoubtedly concealed in these data is the normal impact activity from cosmic dust and probably lunar ejecta, as well. This paper is based on the recognition that the bulk of events registered by the LEAM experiment are not signatures of hypervelocity cosmic dust particles, as expected, but are induced signatures of electrostatically charged and transported lunar fines.


2003 ◽  
Vol 69 (6) ◽  
pp. 485-506 ◽  
Author(s):  
R. V. KENNEDY ◽  
J. E. ALLEN

Probe theory is generally used to find the potential of dust particles immersed in plasma. The orbital motion limited theory (OML) is often used to find the potential at the probe surface, but the assumptions underlying this theory are usually not valid in the case of dust and the more general orbital motion (OM) theory is much harder to calculate. Solutions are given for the OM theory in a range of cases applicable to dust. It is shown that the surface potential the full theory gives reduces to the OML result for small probes. Commonly in dusty plasmas the OML surface potential is used, with the surrounding distribution given by Debye–Hückel, or Yukawa theory. This form, however, neglects ion depletion due to the absorption of particles on the probe surface. In this paper a new analytical solution to the system is given which is applicable to small probes and dust. This new expression is equivalent to Yukawa form, but takes ion absorption into account.


2011 ◽  
Vol 63 (10) ◽  
pp. 1113-1117
Author(s):  
Masanori Kobayashi ◽  
Hideo Ohashi ◽  
Sho Sasaki ◽  
Hiromi Shibata ◽  
Takeo Iwai ◽  
...  

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