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Dust-obscured star formation has dominated the cosmic history of star formation, since z ≃ 4 . However, the recent finding of significant amount of dust in galaxies out to z ≃ 8 has opened the new frontier of investigating the origin of dust also in the earliest phases of galaxy formation, within the first 1.5 billion years from the Big Bang. This is a key and rapid transition phase for the evolution of dust, as galaxy evolutionary timescales become comparable with the formation timescales of dust. It is also an area of research that is experiencing an impressive growth, especially thanks to the recent results from cutting edge observing facilities, ground-based, and in space. Our aim is to provide an overview of the several findings on dust formation and evolution at z > 4 , and of the theoretical efforts to explain the observational results. We have organized the review in two parts. In the first part, presented here, we focus on dust sources, primarily supernovae and asymptotic giant branch stars, and the subsequent reprocessing of dust in the interstellar medium, through grain destruction and growth. We also discuss other dust production mechanisms, such as Red Super Giants, Wolf–Rayet stars, Classical Novae, Type Ia Supernovae, and dust formation in quasar winds. The focus of this first part is on theoretical models of dust production sources, although we also discuss the comparison with observations in the nearby Universe, which are key to put constraints on individual sources and processes. While the description has a general applicability at any redshift, we emphasize the relative role of different sources in the dust build-up in the early Universe. In the second part, which will be published later on, we will focus on the recent observational results at z > 4 , discussing the theoretical models that have been proposed to interpret those results, as well as the profound implications for galaxy formation. [ABSTRACT FROM AUTHOR]

Since the first automatic missions to the Moon, the activity of dust particles from atmosphereless bodies has been recorded. Since then, a lot of theoretical and experimental studies of this effect have been carried out, but at present there is no clear understanding of the influence of external actions on the dynamics of this phenomenon. This paper presents the results of experiments to determine the effect of hard UV radiation on the activity of dust particles, which makes a significant contribution to particle dynamics. The result of determining the conditions for particle removal from the surface is in accordance with theoretical calculations. [ABSTRACT FROM AUTHOR]

The article proposes a new method for estimating the number of particles in experiments on modeling the interaction of cosmic and lunar dust with the surface of spacecraft. The experiments are based on the creation of a dusty plasma cloud, when exposed to radiation from a powerful pulsed gyrotron on a substance simulating cosmic or lunar dust. This approach was tested using a lunar regolith simulator. The dynamics of particles in dust clouds obtained as a result of microwave discharge is analyzed using the ImageJ program. [ABSTRACT FROM AUTHOR]

The relationship between spikes in cosmic dust fluxes onto the Earth's surface (mainly represented by native metal particles) and the behavior of the polarity of the main geomagnetic field has been studied. For this, a search was carried out for horizons of paleodeposits with a high concentration of cosmic dust (exceeding the background concentration by more than an order of magnitude). Such increased concentrations of cosmic dust particles were found in peat deposits corresponding to the Etrussia excursion (2.5–3 ka), as well as in ancient Cretaceous and Paleogene marine deposits. In total, we discovered five horizons with a thickness up to 1 m hosting a high concentration of cosmic dust. Measurements of the paleo‒and petromagnetic parameters of samples selected based on the thickness of sedimentary strata showed that the beginning of accumulation of these horizons coincided with geomagnetic field excursions. In this case, sediment enrichment in dust particles could have lasted somewhat longer than a geomagnetic field excursion. Evidence was obtained that Earth collisions with dense fluxes of cosmic dust could have coincided with short-term disturbances in the polarity of the geomagnetic field, but this had no lasting effect on the geodynamo. [ABSTRACT FROM AUTHOR]

In recent years, evidence has been obtained that in the outer region of the Solar System (in the inner Oort cloud) at a distance of ~300–700 AU from the Sun, there may be a captured planet or a primordial black hole. In this paper, we show that the gravitational scattering on this object of dust particles located in the same region can transfer them to new elongated orbits reaching the Earth's orbit. With the mass of the captured object on the order of 5–10 Earth masses, the calculated dust flow near the Earth is ~0.1–3 µg m–2 year–1 is comparable in order of magnitude with the observed flow. This effect gives a joint restriction on the parameters of the captured object and on the amount of dust in the Oort cloud. [ABSTRACT FROM AUTHOR]

The Hayabusa2 spacecraft succeeded in sampling and returning materials from the C-type, near-Earth asteroid (162173) Ryugu. As part of the Hayabusa2 Initial Analyses, chemical and isotopic compositions of volatile species were measured. The samples analyzed were grains of about 1 mm in diameter and were individually treated without exposure to Earth's atmosphere throughout the entire analytical/experimental processes to minimize alteration and contamination effects by adsorption of Earth's atmosphere or chemical reactions with reactive species such as oxygen and water in Earth's atmosphere. In order to perform spectroscopic and electron-microscopic observations in advance of a series of the isotopic measurements, the sample surface needed to be smoothed. We employed a pelletization method to obtain the required flatness for the returned samples because pelletization is a less sample-consuming method compared to mechanical polishing, microtomy, or ion milling. In order to perform the subsequent analyses, the samples must undergo minimal contamination during the pelletization procedure and be easy to remove from the pelletization tools. Therefore, embedding with resins or low-melting-point metals was not employed. Under these constraints, tools and methods for sample pelletization, handling, and transportation were developed. The tools developed for pelletization and housing also contributed to easier handling of small (less than about 1 mm in diameter) samples. Here we describe the methods and the tools that enable treatment of pristine asteroidal samples under non-atmospheric exposure conditions throughout transportation, weighing, pelletization, and installation into the instruments for chemical and isotopic measurements. The methods and tools we developed can be applied to other small samples including meteorites, cosmic dust, and future returned samples. [ABSTRACT FROM AUTHOR]

Interstellar dust particles were discovered in situ, in the solar system, with the Ulysses mission’s dust detector in 1992. Ever since, more interstellar dust particles have been measured inside the solar system by various missions, providing insight into not only the composition of such far-away visitors, but also in their dynamics and interaction with the heliosphere. The dynamics of interstellar (and interplanetary) dust in the solar/stellar systems depend on the dust properties and also on the space environment, in particular on the heliospheric/astrospheric plasma, and the embedded time-variable magnetic fields, via Lorentz forces. Also, solar radiation pressure filters out dust particles depending on their composition. Charge exchanges between the dust and the ambient plasma occur, and pick-up ions can be created. The role of the dust for the physics of the heliosphere and astrospheres is fairly unexplored, but an important and a rapidly growing topic of investigation. This review paper gives an overview of dust processes in heliospheric and astrospheric environments, with its resulting dynamics and consequences. It discusses theoretical modeling, and reviews in situ measurements and remote sensing of dust in and near our heliosphere and astrospheres, with the latter being a newly emerging field of science. Finally, it summarizes the open questions in the field. [ABSTRACT FROM AUTHOR]

2720 cosmic spherules extracted from ferromanganese crusts sampled at two guyots of the Magellan Seamounts were studied using a scanning electron microscope. In comparison with collections of modern cosmic spherules, our samples are significantly richer in I-type spherules (consisting of Fe oxides, often with a Fe–Ni metal core). The compositions of 406 metal cores were analyzed. Six spherules with cores significantly enriched in Co (>5 wt %) were found; these were the first spherules of this composition ever found worldwide. Such a high Co content in the cores cannot be explained by the evolution of a micrometeorite of chondrite composition at its melting. Some groups of the spherules have either elevated or lower Co concentrations than those expected according to the evolutionary trend of spherules at oxidation during the atmosphere entry. These groups apparently reflect the composition of the initial micrometeorites. It is proposed to use the composition of the cores of cosmic spherules to reveal the time variation in the composition of cosmic dust entering the Earth. Several spherules were found with small cores compared to the oxide shell; these cores are characterized by the presence of a significant amount of platinum group elements (PGE) (up to 2.4 wt % PGE). The averaged composition of PGE in the high-Ni core, which is the richest in PGE, shows a pattern close to that of chondrite. The collection contains 23 spherules that host PGE nuggets. In three spherules, micrometer-sized nuggets with various PGE were found (one nugget is Os + Ir + Ru, and two others contain all PGE). In 20 spherules, nanometer-sized nuggets of rhodium platinum were found. The largest nugget (3 μm) has PGE ratios close to chondritic, with the exception of a significant depletion in Pd. [ABSTRACT FROM AUTHOR]

The influence of the multilayer structure of cosmic dust ice mantles on the chemical processes occurring in them before, during and after protoplanetary disc ourbursts is considered. At the stage preceding the disc formation, consideration of the differences between the surface and the bulk ice is not so important, but after the formation of the disc, the features of chemical processes in different layers of the mantle become more significant. In particular, in the three-phase model (gas, mantle surface, bulk ice), compared to the two-phase model, the number of potential outburst indicators that retain "atypical" abundances for hundreds of years after the end of the outburst increases. The only species that is outburst sensitive in the two-phase model and insensitive to it in the three-phase model is adsorbed formamide (gNH2CHO). [ABSTRACT FROM AUTHOR]

In this work, we have revealed a new model emerged from the restricted three-body problem within a framework of a non-isotropic variation of mass. This variation is taken when the escaping or incoming mass occurs from points of an infinitesimal body. The collinear, triangular and out-of-plane equilibrium points are determined in the cases of and , as well as graphical investigations are shown when . We demonstrate that this model can be applied to explore small objects such as cosmic dust or grains. It also has interesting applications for future space colonization and the parking of vehicles and spacecraft. Moreover, it can be used to study the dynamics of Earth–Moon rocket system. [ABSTRACT FROM AUTHOR]

The ionization-type cosmic dust detector METEOR-L is being developed for the lunar orbiter Luna-26 and is designed to study the distribution of meteoric bodies in space by mass and velocity, and for long-term monitoring of the dynamic evolution of the dust component in the lunar exosphere. Recent studies of dust clouds around the Moon show a close relationship between the constant and dynamic evolution of the components of the lunar exosphere, the geological history of the formation of the lunar regolith, the processes of formation and accumulation of volatiles in the lunar regolith with the constant impact of such components of the interplanetary medium as interplanetary dust of predominantly cometary origin and meteoroids from the belt asteroids. The cosmic dust detector is capable of registering meteoric particles 0.1–3 μm in size with a mass of 10–14–10–9 g and speeds from 3 to 35 km s–1. Tests and calibration at a particle accelerator have confirmed the declared functionality of the detector for detecting cosmic dust particles with parameters characteristic of the lunar exosphere. [ABSTRACT FROM AUTHOR]

An in-situ cosmic-dust instrument called the Mercury Dust Monitor (MDM) had been developed as a part of the science payload for the Mio (Mercury Magnetospheric Orbiter, MMO) stage of the joint European Space Agency (ESA)–JAXA Mercury-exploration mission. The BepiColombo spacecraft was successfully launched by an Ariane 5 rocket on October 20, 2018, and commissioning tests of the science payload were successfully completed in near-earth orbit before injection into a long journey to Mercury. MDM has a sensor consisting of four plates of piezoelectric lead zirconate titanate (PZT), which converts the mechanical stress (or strain) induced by dust-particle impacts into electrical signals. After the commencement of scientific operations, MDM will measure the impact momentum at which dust particles in orbit around the Sun collide with the sensor and record the arrival direction. This paper provides basic information concerning the MDM instrument and its predicted scientific operation as a future reference for scientific articles concerning the MDM’s observational data. [ABSTRACT FROM AUTHOR]

The mass spectra of astronomical objects of various kinds are compared: cosmic dust, asteroids, planets, stars, star clusters, galaxies, and galactic clusters. The authors have previously noted a similarity in the (initial) mass functions for relatively massive objects (stars, galaxies, galactic clusters). In this paper the range of masses of astronomical objects is extended to the limit and covers roughly 68 orders of magnitude. It is confirmed that the initial mass spectra of objects in ensembles formed by fragmentation (a fast process) may, in a first approximation in a statistically significant range be represented by a basis (reference) function dN / dM ∞ M-2, where dN is the number of objects in a range [M, M+dM] of masses. The significance of this function is the probability density of formation of objects, which total mass in a range [d ln M] of masses is independent of the mass M or, in other words, reduces to the absence of a distinct mass scale. The physical reasons determining the deviation of the initial mass functions from the reference function are discussed briefly. It is noted that the mass spectra in ensembles of objects formed by mergers (coagulation in the case of dust), i.e., in a relatively slow evolutionary process, can also be of a form close a reference function. The main reason for this universality lies in the random character of the processes of formation and evolution of these ensembles of astronomical objects. [ABSTRACT FROM AUTHOR]

One of the probable sources of water and other volatiles, forming ice deposits in the shadowed polar regions of the Moon, is cosmic matter delivered by comets and asteroids, as well as by cosmic dust. In this connection, we estimated the contribution of volatile components to the material received due to micrometeoroid bombardment. From the estimates of the current flux of micrometeoroids to the Earth and the Moon, we determined a probable range for the rate of the cosmic dust accretion to the Moon as 6.19 × 10–13 to 14.74 × 10–13 g/m2 s. Based on the mean value of this rate, the mass of fallen micrometeoroids is equal to the total mass of cosmic matter delivered to the Moon by bodies 3 m to 4 km in size. Taking into consideration that the largest fraction (~90%) of the mass of micrometeoroids is represented by the material that is close to CM- and CI-type carbonaceous chondrites in composition, we estimated the amounts of released water and other components and volatile elements. The obtained values are close to the amount of water introduced by comets. [ABSTRACT FROM AUTHOR]

The possible relationship between the 60-year variation in global temperature with an amplitude of 0.35°C and the corresponding cycle at the location of Jupiter and Saturn is considered. It was shown that the gravitational perturbation of the Earth's orbit by Jupiter and Saturn can only account for a global temperature variation of only 0.012°C. It is shown that the modulation of the flux of cosmic dust entering the Earth's atmosphere by the gravitational field of Jupiter and Saturn is a more promising mechanism for the transmission of the influence of giant planets on the Earth's climate. In order for the global temperature to experience variation with an amplitude of 0.3°C, Jupiter and Saturn must provide a variation in the flux of extraterrestrial matter in the Earth's atmosphere with an amplitude of 16%. The question of whether these two planets are capable of providing such a variation is of considerable interest for climatology. [ABSTRACT FROM AUTHOR]

More than 250 magnetic spherules 40–200 µm in size were mechanically separated from a ferromanganese crust sample of Fedorov Guyot in the Magellan Seamounts. The composition of the spherules corresponds to stony-iron and iron (with a nickel admixture) meteorites oxidized to varying degrees. The surface morphology and the internal texture of these spherules are similar to modern micrometeorites. Some spherules have a zonal structure with a core consisting of unoxidized nickel iron, with a nickel content of 7.5%–53% and a cobalt admixture up to 3.7%. Microinclusions (up to 0.5 μm) of rhodium platinum were found for the first time in a spherule consisting of wüstite and magnetite in the ferromanganese crust. The presence of cosmogenic spherules in the sample studied indicates the accumulation of a certain fraction of platinoids in the ferromanganese crusts due to the burial of cosmic dust in them. [ABSTRACT FROM AUTHOR]

Just as geological samples from Earth record the natural history of our planet, astromaterials hold the natural history of our solar system and beyond. Astromaterials acquisition and curation practices have direct consequences on the contamination levels of astromaterials and hence the types of questions that can be answered about our solar system and the degree of precision that can be expected of those answers. Advanced curation was developed as a cross-disciplinary field to improve curation and acquisition practices in existing astromaterials collections and for future sample return activities, including meteorite and cosmic dust samples that are collected on Earth. These goals are accomplished through research and development of new innovative technologies and techniques for sample collection, handling, characterization, analysis, and curation of astromaterials. In this contribution, we discuss five broad topics in advanced curation that are critical to improving sample acquisition and curation practices, including (1) best practices for monitoring and testing of curation infrastructure for inorganic, organic, and biological contamination; (2) requirements for storage, processing, and sample handling capabilities for future sample return missions, along with recent progress in these areas; (3) advancements and improvements in astromaterials acquisition capabilities on Earth (i.e., the collection of meteorites and cosmic dust); (4) the importance of contamination knowledge strategies for maximizing the science returns of sample-return missions; and (5) best practices and emerging capabilities for the basic characterization and preliminary examination of astromaterials. The primary result of advanced curation research is to both reduce and quantify contamination of astromaterials and preserve the scientific integrity of all samples from mission inception to secure delivery of samples to Earth-based laboratories for in-depth scientific analysis. Advanced curation serves as an important science-enabling activity, and the collective lessons learned from previous spacecraft missions and the results of advanced curation research will work in tandem to feed forward into better spacecraft designs and enable more stringent requirements for future sample return missions and Earth-based sample acquisition. [ABSTRACT FROM AUTHOR]

The results of laboratory mass-spectrometer studies of the laser-induced dissociation of molecules of simple aromatic hydrocarbons adsorbed on a quartz substrate under the conditions of deep vacuum and low temperatures are adapted to the physical and chemical conditions in regions of active star formation in molecular clouds. The main properties of the photolysis of physically adsorbed molecules compared to the photodissociation of isolated molecules in the gas phase are identified. The relevance of molecular photolytic desorption to the real conditions in the interstellar medium is analyzed, in particular, to the conditions in photodissociation regions. It is shown that the photodissociation of adsorbed benzene occurs along other channels and with appreciably lower efficiency than does the corresponding process in the gas phase. The photodissociation of aromatic hydrocarbons adsorbed on the surfaces of interstellar grains cannot make a large contribution to the abundance of hydrocarbons with small numbers of atoms observed in the interstellar medium. [ABSTRACT FROM AUTHOR]

Peat cores sampled from different climatic zones are studied. The petromagnetic and microprobe methods are used to find peat layers enriched with cosmic dust. It is established that the behavior of saturation isothermal remanent magnetization (SIRM) of peat deposits from the zones where the aeolian transfer of terrigenous particles is negligible can be used for studying the dynamics of the fall of cosmic matter on the Earth's surface. The cosmic dust flux can be conditionally divided into the background and burst components. Here, the background flux of cosmic dust varies cyclically. The characteristic times of these cycles are about 100 years. The cyclicity in the background flux of cosmic material most clearly manifested itself in the interval of 1200 to 500 years ago. The most significant burst in the influx of cosmic material (by an order of magnitude above the background) is revealed in the layer that was formed about 5000 years ago. The microprobe studies established that the mineralogical content of cosmic dust differs between the background and burst fluxes. [ABSTRACT FROM AUTHOR]

Abstract: 185 fine-grained micrometeorites (FgMMs) from the Novaya Zemlya micrometeorite collection were studied to elucidate the sources of cosmic dust. The compositions of the micrometeorites were compared with those of carbonaceous chondrites and cosmic spherules. FgMMs were weakly or moderately heated when decelerated in the atmosphere, and some of them thereby retained their original textures (unmelted FgMMs), while others consist mostly of porous degassing products of phyllosilicates (scoriaceous FgMMs). According to the composition of their matrix, we divide the FgMMs into two groups: high- and low-Fe. The textures and compositions of the FgMMs are generally similar to those of the matrix of carbonaceous chondrites. The FgMM group with high-Fe matrix corresponds to the composition of CI, CM, CO, and CR chondrites, which may have been a source of these meteorites. Conversely, the low-Fe group of FgMMs differs from chondrites of these groups and is likely related to the carbonate-poor matrix of the Tagish Lake carbonaceous chondrite or is presented by a material that is still absent from meteorite collections. We have compared the compositions of the FgMMs with the compositions of various types of cosmic spherules (CSs), which were produced by melting of micrometeoroids (cosmic dust particles) at their deceleration in the atmosphere. Both original and published data on CS compositions are used. Porphyritic and barred textural varieties of CSs could have been produced from micrometeoroids similar in the compositions to the high-Fe FgMMs, whereas low-Fe micrometeoroids might have been precursors of cryptocrystalline and glass CSs. [ABSTRACT FROM AUTHOR]

We have performed the calculations of the orbital evolution of dust particles from volcanic glass (p-obsidian), basalt, astrosilicate, olivine, and pyroxene in the sublimation zone near the Sun. The sublimation (evaporation) rate is determined by the temperature of dust particles depending on their radius, material, and distance to the Sun. All practically important parameters that characterize the interaction of spherical dust particles with the radiation are calculated using the Mie theory. The influence of radiation and solar wind pressure, as well as the Poynting-Robertson drag force effects on the dust dynamics, are also taken into account. According to the observations (Shestakova and Demchenko, 2016), the boundary of the dust-free zone is 7.0-7.6 solar radii for standard particles of the zodiacal cloud and 9.1-9.2 solar radii for cometary particles. The closest agreement is obtained for basalt particles and certain kinds of olivine, pyroxene, and volcanic glass. [ABSTRACT FROM AUTHOR]

As low- and intermediate-mass stars reach the asymptotic giant branch (AGB), they have developed into intriguing and complex objects that are major players in the cosmic gas/dust cycle. At this stage, their appearance and evolution are strongly affected by a range of dynamical processes. Large-scale convective flows bring newly-formed chemical elements to the stellar surface and, together with pulsations, they trigger shock waves in the extended stellar atmosphere. There, massive outflows of gas and dust have their origin, which enrich the interstellar medium and, eventually, lead to a transformation of the cool luminous giants into white dwarfs. Dust grains forming in the upper atmospheric layers play a critical role in the wind acceleration process, by scattering and absorbing stellar photons and transferring their outward-directed momentum to the surrounding gas through collisions. Recent progress in high-angular-resolution instrumentation, from the visual to the radio regime, is leading to valuable new insights into the complex dynamical atmospheres of AGB stars and their wind-forming regions. Observations are revealing asymmetries and inhomogeneities in the photospheric and dust-forming layers which vary on time-scales of months, as well as more long-lived large-scale structures in the circumstellar envelopes. High-angular-resolution observations indicate at what distances from the stars dust condensation occurs, and they give information on the chemical composition and sizes of dust grains in the close vicinity of cool giants. These are essential constraints for building realistic models of wind acceleration and developing a predictive theory of mass loss for AGB stars, which is a crucial ingredient of stellar and galactic chemical evolution models. At present, it is still not fully possible to model all these phenomena from first principles, and to predict the mass-loss rate based on fundamental stellar parameters only. However, much progress has been made in recent years, which is described in this review. We complement this by discussing how observations of emission from circumstellar molecules and dust can be used to estimate the characteristics of the mass loss along the AGB, and in different environments. We also briefly touch upon the issue of binarity. [ABSTRACT FROM AUTHOR]

In this paper we analyze the dynamical behavior of large dust grains in the vicinity of a cometary nucleus. To this end we consider the gravitational field of the irregularly shaped body, as well as its electric and magnetic fields. Without considering the effect of gas friction and solar radiation, we find that there exist grains which are static relative to the cometary nucleus; the positions of these grains are the stable equilibria. There also exist grains in the stable periodic orbits close to the cometary nucleus. The grains in the stable equilibria or the stable periodic orbits won't escape or impact on the surface of the cometary nucleus. The results are applicable for large charge dusts with small area-mass ratio which are near the cometary nucleus and far from the Solar. It is found that the resonant periodic orbit can be stable, and there exist stable non-resonant periodic orbits, stable resonant periodic orbits and unstable resonant periodic orbits in the potential field of cometary nuclei. The comet gravity force, solar gravity force, electric force, magnetic force, solar radiation pressure, as well as the gas drag force are all considered to analyze the order of magnitude of these forces acting on the grains with different parameters. Let the distance of the dust grain relative to the mass centre of the cometary nucleus, the charge and the mass of the dust grain vary, respectively, fix other parameters, we calculated the strengths of different forces. The motion of the dust grain depends on the area-mass ratio, the charge, and the distance relative to the comet's mass center. For a large dust grain (> 1 mm) close to the cometary nucleus which has a small value of area-mass ratio, the comet gravity is the largest force acting on the dust grain. For a small dust grain (< 1 mm) close to the cometary nucleus with large value of area-mass ratio, both the solar radiation pressure and the comet gravity are two major forces. If the a small dust grain which is close to the cometary nucleus have the large value of charge, the magnetic force, the solar radiation pressure, and the electric force are all major forces. When the large dust grain is far away from the cometary nucleus, the solar gravity and solar radiation pressure are both major forces. [ABSTRACT FROM AUTHOR]

The model is constructed to describe the Schwarzschild-like black hole enclosed in the dust cosmological background. It is an exact solution of Einstein equations for spherically symmetric dust distribution, and is a special case of Lemaitre-Tolman-Bondi solutions. The motion of the test particle in the model is investigated in comoving coordinate frame. Observable velocity of the particle is found from geodesic equations. It is shown that chosen reference system does not allow to solve the problem of 'all or nothing' behavior. [ABSTRACT FROM AUTHOR]

This work is about the identification of modern cosmic dust that had survived heating during its high-velocity passage through the Earth's atmosphere from He isotope concentrations in marine (Gulf of Finland) ferromanganese nodules (FMNs). The measured bulk composition of helium includes components of various origins, enabling the determination of the age (1800 years) of the shallow-water Baltic FMNs and the average time of exposure (8 × 10 years) of cosmic dust particles during their existence in space. The concentration of cosmic dust per gram of FMN material is found to be 0.036 μg. The contribution of solar-wind helium to the Earth's atmospheric helium is found to be small. The experiments are conducted by the stepheating method in vacuo with the subsequent mass-spectrometric analysis of the helium released from the samples. [ABSTRACT FROM AUTHOR]

The conditions for the destruction of dust in hot gas in galaxy clusters are investigated. It is argued that extinction measurements can be subject to selection effects, hindering their use in obtaining trustworthy estimates of dust masses in clusters. It is shown, in particular, that the ratio of the dust mass to the extinction M / S increases as dust grains are disrupted, due to the rapid destruction of small grains. Over long times, this ratio can asymptotically reach values a factor of three higher than the mean value in the interstellar medium in the Galaxy. This lowers dust-mass estimates based on measurements of extinction in galaxy clusters. The characteristic lifetime of dust in hot cluster gas is determined by its possible thermal isolation by the denser medium of gas fragments within which the dust is ejected from galaxies, and can reach 100-300 million years, depending on the kinematics and morphology of the fragments. As a result, the mass fraction of dust in hot cluster gas can reach 1-3% of the Galactic value. Over its lifetime, dust can also be manifest through its far-infrared emission. The emission characteristics of the dust change as it is disrupted, and the ratio of the fluxes at 350 and 850 μm can increase appreciably. This can potentially serve as an indicator of the state of the dust and ambient gas. [ABSTRACT FROM AUTHOR]

The problem of determining the phase-space distribution function for the system of the noninteracting dust particles for the mathematical model of cosmic dust Kordylewski clouds-clusters of the non-interacting dust particles in the vicinity of the triangular libration points of the Earth-Moon-Particle system taking into account perturbations from the Sun was considered. [ABSTRACT FROM AUTHOR]

The results of modeling of the distribution of dust in the circumsolar zone are presented. The dust distribution was retrieved from observations of the line-of-sight velocities in the F-corona to the distances of 7-11 solar radii during the total eclipses of the Sun in different years: on July 31, 1981; August 11, 1991; March 29, 2006; and August 1, 2008. Comparison of the results has shown that the dust composition varies from year to year and the dust is dynamically nonuniform. In addition to the dust related to the zodiacal cloud and concentrating to the ecliptic plane, the dust of retrograde motion and the ejections and accretion in the polar regions are observed. From the results of observations of eclipses on July 31, 1981, August 11, 1991, and August 1, 2008, the east-west asymmetry in a sign of the line-of-sight velocities was detected: they are negative to the east of the Sun and positive to the west. Such distribution of the velocities is indicative of the nearecliptic orbital dust motion, whose direction coincides with that of the motion of the planets. In the course of the eclipse of March 29, 2006, almost no dynamical connection with the zodiacal cloud was found. At the same time, the direction, where the observed velocities are largest in value and opposite in sign on opposite sides of the Sun, was determined, which provides evidence of the orbital motion deviating from the ecliptic plane. The results of observations in 2006 reveal a clear genetic connection of the observed orbital motion of dust with the parent comets of the Kreutz family found near the Sun close to the eclipse date. The velocities observed near the symmetry line in the plane of the sky grow by absolute value with increasing the elongation, which may take place, if the line of sight croßses an empty zone that is free of dust. The modeling of the data of observations near the symmetry plane allowed the parameters of the dust distribution near the sublimation zone to be obtained. In 2006, the 'black' cometary dust with a low albedo ( A = 0.05) was observed; it showed high values of the power-law exponents in the distance distribution of the dust concentration ( V = 2.2 > 1) and in the size distribution of grains (γ = 5.2 > 4.0) and a strong radiation pressure (β = 0.70-0.74). We estimated the mean radius of grains as ≈0.8-0.9 µm and the radius of the dust-free zone as ≈9.1-9.2 solar radii. The latter corresponds to the distances, where the low-melt components of olivines and pyroxenes disintegrate. In 2008, the observed zodiacal dust concentrating to the ecliptic plane demonstrated the canonical parameters: A = 0.1-0.2, V ≈ 1, ß ≈ 0, γ = 4.0, the mean radii of grains were 0.9-1.2 µm, and the radius of the dust-free zone was 7.0-7.6 solar radii. [ABSTRACT FROM AUTHOR]

The fabrication of an ultralow-density hydrophobic silica aerogel for the intact capture cosmic dust during the Tanpopo mission is described. The Tanpopo experiment performed on the International Space Station orbiting the Earth includes the collection of terrestrial and interplanetary dust samples on a silica aerogel capture medium exposed to space for later ground-based biological and chemical analyses. The key to the mission's success is the development of high-performance capture media, and the major challenge is to satisfy the mechanical requirements as a spacecraft payload while maximizing the performance for intact capture. To this end, an ultralow-density (0.01 g cm) soft aerogel was employed in combination with a relatively robust 0.03 g cm aerogel. A procedure was also established for the mass production of double-layer aerogel tiles formed with a 0.01 g cm surface layer and a 0.03 g cm open-topped, box-shaped base layer, and 60 aerogel tiles were manufactured. The fabricated aerogel tiles have been demonstrated to be suitable as flight hardware with respect to both scientific and safety requirements. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The paper reports scanning electron microscopy (FEG-SEM) and transmission electron microscopy (TEM) data on three cryptocrystalline (CC) cosmic spherules of chondritic composition (Mg/Si ≈ 1) from two collections taken up at glaciers at the Novaya Zemlya and in the area of the Tunguska event. The spherules show 'brickwork' microtextures formed by minute parallel olivine crystals set in glass of pyroxene-plagioclase composition. The bulk-rock silicate chemistry, microtexture, mineralogy, and the chemical composition of the olivine and the local chemistry of the glass in these spherules testify to a chondritic source of the spherules. The solidification of the spherules in the Earth's atmosphere was proved to be a highly unequilibrated process. A metastable state of the material follows, for example, from the occurrence of numerous nanometer-sized SiO globules in the interstitial glass. These globules were formed by liquid immiscibility in the pyroxene-SiO system. Troilite FeS and schreibersite (Fe,Ni)P globules were found in the FeNi metal in one of the spherules, which suggests that the precursor was not chemically modified when melted in the Earth's atmosphere. Our results allowed us to estimate the mineralogy of the precursor material and correlate the CC spherules with the chondrule material of chondrites. The bulk compositions of the spherules are closely similar to those of type-IIA chondrules. [ABSTRACT FROM AUTHOR]

As a result of the next cycle of our long-term monitoring, we present our UBV JHKLM photometry for the symbiotic nova V1016 Cyg in 2008-2014. The star continued to systematically fade and redden in UBV: over this period, the brightness declined by 0 ṃ1 in V and by 0 ṃ2 in B and U, the B-V color index increased by 0 ṃ1, and U-B barely changed. On the color-color ( U-B, B-V) diagram, the star moved approximately horizontally rightward with a slight bluing in U-B starting from 2000. Our JHKLM photometry has shown a decline in the mean infrared (IR) brightness and a rise in the mean IR color indices after 2004 due to an increase in the optical depth of the dust envelope. The brightness decline and reddening of the Mira in the near infrared reached their extreme values over the entire period of the system's observations by the end of 2014. The pulsation period of the Mira is determined with confidence: P = 465 ± 5 days. The distance to the Mira, D = 2.92 ± 0.16 kpc, and its parameters, the radius R = (470 ± 50) R and luminosity L = (9200 ± 1900) L, have been estimated from the observations of V1016 Cyg at its maximum J brightness and at its minimum J-H color index. The temperature of the star during its pulsations varied within the range T = 2100-2700 K.We have estimated the parameters of the dust envelope near its maximum (in 2004) and minimum (in 2012-2014) IR brightness. The mass of the dust envelope almost doubled in ten years, with the rate of dust supply being Δ M ∼ 10 M yr. Using a low-resolution spectrograph, we performed absolute spectrophotometry for V1016 Cyg in 1995-2013 in the range λ4340-7130 Å. We have shown that almost all absolute fluxes in lines and in continuum at λ4400 Å decrease monotonically after 2000, while the relative intensities of [O III], [Fe VII], and [Ca VII] lines increase after the minimum that probably occurred in the 1990s. The significant (approximately by a factor of 10 from 1995 to 2013) decrease of the flux in the Raman O VI λ6825 line reflects a change of conditions in the formation zone of this line due to the absorption of some O VI λ1032 photons in the newly forming dust envelope of the cool component. [ABSTRACT FROM AUTHOR]

The results provided by the microprobe and thermomagnetic studies of native iron in sediments are generalized. It is found that the sediments are abundant in Ni-free iron particles. These particles are shown to have extraterrestrial origin and likely to be parts of cosmic dust. It is suggested that these particles were formed from the mantle and crustal rocks as a result of their fragmentation and melting of the silicates (such as olivine and pyroxene) contained in these rocks. [ABSTRACT FROM AUTHOR]

The present work introduces the hypothesis of existence of a hardly detectable component of the interplanetary dust cloud and demonstrates that such a component is a dust formation consisting of the dust particles of nano-metric dimensions. This work describes the main physical properties of such a kind of nano-dust, and its possible chemical and mineralogical peculiarities proposes new explanations related to reddening of the dynamically cold transneptunian objects on account of scattering their light by nano-dust of the hardly detectable component of the interplanetary dust cloud. We propose the relation for the coefficient of absorption by the nano-dust and provide results of the statistical analysis of the TNO color index-orbital inclinations. We also present a critical assessment of the proposed hypothesis. [ABSTRACT FROM AUTHOR]

From the dynamic modeling of the process forming the dust tail of comet C/2012 K5 (LINEAR), the brightness distribution in this dust tail has been retrieved. The model developed by Korsun on the basis of the statistical Monte-Carlo approach was used. The adequacy of the model was determined by fitting the observed and modeled isophots. The following parameters of dust particles composing the dust component of the cometary atmosphere have been estimated: the range of radii (0.7-100 μm), the power index of the size distribution law (-2.4), the range of velocities (6-135 m/s), and the maximum age of dust particles (88 days). [ABSTRACT FROM AUTHOR]

The question of occurrence of cosmic dust clouds, which were found by Kordylewski in 1961 in the vicinity of libration point L of the Earth-Moon system, still causes debates and concern. We explain theoretically the phenomenon of the apparent vanishing and appearance of the Kordylewski cosmic dust clouds in the vicinity of triangular libration points L and L of the Earth-Moon system. The possibility of occurrence of two such clouds rotating around libration points L and two clouds rotating around point L is shown and optimal times for their observation from the Earth are determined. The investigation is performed based on analysis of a stable periodic motion in a planar restricted circular problem of three bodies, Earth-Moon-Particle, allowing for perturbations from the Sun under the assumption that the orbits of the Earth and Moon are circular and lie in one plane. [ABSTRACT FROM AUTHOR]

In this paper, we report the progress in developing a silica-aerogel-based cosmic dust capture panel for use in the Tanpopo experiment on the International Space Station (ISS). Previous studies revealed that ultralow-density silica aerogel tiles, comprising two layers with densities of 0.01 and 0.03 g/cm developed using our production technique, were suitable for achieving the scientific objectives of the astrobiological mission. A special density configuration (i.e., box framing) aerogel with a holder was designed to construct the capture panels. Qualification tests for an engineering model of the capture panel as an instrument aboard the ISS were successful. Sixty box-framing aerogel tiles were manufactured in a contamination-controlled environment. [ABSTRACT FROM AUTHOR]

A reductive perturbation technique is employed to investigate the contribution of higher-order nonlinearity and dissipation to nonlinear dust-ion-acoustic (DIA) shock waves in a three-component degenerate dense space plasma. The model consists of degenerate electron (being either ultrarelativistic or nonrelativistic), nonrelativistic ion fluid and stationary heavy dust grains. A nonlinear Burger equation and a linear inhomogeneous Burger-type equation are derived. The present model admits only compressive DIA shocks. Including these higher-order corrections results in creating new solitary wave structures ' humped DIA shock' waves. For the case of ultrarelativistic (nonrelativistic) electrons, one (two) humped DIA shock is (are) created. The DIA shock wave amplitude and velocity is larger in case of ultrarelativistic electrons than of nonrelativistic electrons. It is shown that the effects of kinematic viscosity, heavy dust grains number density, and equilibrium ion number density have important roles in the basic features of the produced DIA shocks and the associated electric fields. The implications of our results to dense plasmas in astrophysical objects (e.g., non-rotating white dwarf stars) are briefly discussed. [ABSTRACT FROM AUTHOR]

A continuous transition from early Friedmann-like radiation era through to late time cosmic acceleration passing through a long Friedmann-like matter dominated era followed by a second phase of radiation era has been realized in modified theory of gravity containing a combination of curvature squared term, a linear term, a three-half term and an ideal fluid. Thus the history of cosmic evolution is explained by modified theory of gravity singlehandedly. The second phase of radiation-like era might provide an explanation to the hydrogen and helium reionization at low redshift. [ABSTRACT FROM AUTHOR]

Galaxies observed at redshift z > 6, when the Universe was less than a billion years old, thus far very rarely show evidence of the cold dust that accompanies star formation in the local Universe, where the dust-to-gas mass ratio is around one per cent. A prototypical example is the galaxy Himiko (z = 6.6), which-a mere 840 million years after the Big Bang-is forming stars at a rate of 30-100 solar masses per year, yielding a mass assembly time of about 150 × 106 years. Himiko is thought to have a low fraction (2-3 per cent of the Sun's) of elements heavier than helium (low metallicity), and although its gas mass cannot yet be determined its dust-to-stellar mass ratio is constrained to be less than 0.05 per cent. The local dwarf galaxy I Zwicky 18, which has a metallicity about 4 per cent that of the Sun's and is forming stars less rapidly (assembly time about 1.6 × 109 years) than Himiko but still vigorously for its mass, is also very dust deficient and is perhaps one of the best analogues of primitive galaxies accessible to detailed study. Here we report observations of dust emission from I Zw 18, from which we determine its dust mass to be 450-1,800 solar masses, yielding a dust-to-stellar mass ratio of about 10−6 to 10−5 and a dust-to-gas mass ratio of 3.2-13 × 10−6. If I Zw 18 is a reasonable analogue of Himiko, then Himiko's dust mass must be around 50,000 solar masses, a factor of 100 below the current upper limit. These numbers are quite uncertain, but if most high-z galaxies are more like Himiko than like the very-high-dust-mass galaxy SDSS J114816.64 + 525150.3 at z ≈ 6, which hosts a quasar, then our prospects for detecting the gas and dust inside such galaxies are much poorer than hitherto anticipated. [ABSTRACT FROM AUTHOR]

Our interest is to study the sheath formation in an inhomogeneous plasma coexisting with an interaction of weak ionization. Pseudopotential analysis has been employed to derive the coherent structures of sheath in plasma. It has shown that the ionization affects the growth of sheath in plasma and nature depends fully on plasma constituents as well. After getting a robust sheath, dynamical behaviors of a levitated dust grain into the robust sheath has been studied which, in fact, leads to find the variation of dust potential, dust sizes along with the net force generated on grains. Results are obtained numerical for some typical plasma parameters. It has demonstrated that the plasma constituent effects the clustering of dust grains in different region within the sheath as a result of which dust agglomeration forms nebulons: patches of dust cloud-like structures with changing fleece. [ABSTRACT FROM AUTHOR]

Properties of propagation of large amplitude dust ion-acoustic solitary waves and double layers are investigated in electron-positron-ion plasma with highly charged negative dust. Sagdeev pseudopotential method has been used to derive the energy balance equation. The expression for the critical Mach number (lower/upper limit) for the existence of solitary structures has also been derived. The Sagdeev pseudopotential is a function of numbers of physical parameters such as ion temperature ( σ), positron density ( δ), dust density ( δ) and electron to positron temperature ratio ( β). These parameters significantly influence the properties of the solitary structures and double layers. Further it is found that both polarity (compressive and rarefactive) solitons and negative potential double layers are observed. [ABSTRACT FROM AUTHOR]

The observed relation between the interstellar linear polarization curve parameters K and λ characterizing the width and the wavelength of the polarization maximum, respectively, is interpreted quantitatively. We have considered 57 stars located in four dark clouds with evidence of star formation: in Taurus, Chamaeleon, around the stars ρ Oph and R CrA. In our modeling we have used the spheroidal dust grain model applied previously to simultaneously interpret the interstellar extinction and polarization curves in a wide wavelength range. The observed trend K ≈ 1.7 λ is shown to be most likely related to the growth of dust grains due to coagulation rather than accretion. The relationship of the interstellar polarization curve parameters K and λ to the mean dust grain size is discussed. [ABSTRACT FROM AUTHOR]

High-resolution multi-archive studies have been promoted to reveal abrupt discontinuities that would express rapid social reactions (days to decades) to sudden exceptional geogenic phenomena (climatic, volcanic, tectonic, geomorphic, or cosmic). We expose here how we have adopted this approach for examining the causal linkages between a series of cultural discontinuities encountered through the cultural deposits of Da'de (Syria) and cosmic airbursts. Cosmic events, known to be rare, erratic, and unpredictable, are traced by exceptional debris that formed from aerosols when violently compressed during entry through the earth atmosphere of hypervelocity cosmic collider. They consist of singular organo-mineral materials in the form of volatile-rich hydrocarbon fuel with resistant metal-rich carbonaceous composites and colorful polymers. The archaeological sequence comprises Da'de phases 0 to III that represent a nearly continuous accumulation for 1,000 years during the Pre-pottery Neolithic period (ca. 9,900-8,900 years bp) and two short-term occupation phases during the pre-Halaf (Da'de IV) and early Bronze Age periods (Da'de V). Study of the exceptional debris in virgin soils and occupation deposits at Da'de has allowed to distinguish an intact debris assemblage that pulverized at the ground following an airburst (type 1 natural singular signal) with the ones that have been processed by humans (type 2 anthropic singular signal). Type 1 singular organo-mineral materials were found intact at the contact of the virgin soil with the earliest Pre-pottery Neolithic A (PPNA) occupation layers (Da'de phase 0, area [SB]), at the top part of the virgin soil with the PPNA occupation layers (Da'de phase Ia, area [B]) and just under the lower slabs of the EB III/IV burials (Da'de phase V, area [SB]). This has allowed to establish a strict contemporaneity between cosmic airbursts and remarkable historical events: initial settlement at phase 0, establishment of the magnificent communal building at phase 1, EBIII/IV cemetery after a long period of abandonment. Evidence for the collection of the singular materials (type 2) and meticulous processing of the related hydrocarbon fuel in occupation floors, earthen construction, coloring materials, and objects have been traced from the initial settlement (phase 0) through the successive cultural periods. This correlation has revealed a long-lasting transmission of the value of memorial natural resources which were only available from time to time in the surroundings. The close timing between changes in the use of the singular organo-mineral materials (preparation techniques, types of by-products) and cultural phases has enabled us to identify social discontinuities which correlate to distinctive geogenic events and search of the related exceptional resources. Based on the long-term record from Da'de, cosmic airbursts are suggested to be considered as a new class of dual-discontinuous signal of historical dimension, which have led to sudden (days to months) geogenic shifts in the availability of singular fuel resources and, simultaneously, to rapid cultural responses in their exploitation and use, depending on reactivity of local landscapes to the induced changes at short time scales (decades). [ABSTRACT FROM AUTHOR]

Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts-that is, increased rates of star formation-in the most massive dark-matter haloes at early epochs. However, it remains unknown how soon after the Big Bang massive starburst progenitors exist. The measured redshift (z) distribution of dusty, massive starbursts has long been suspected to be biased low in z owing to selection effects, as confirmed by recent findings of systems with redshifts as high as ∼5 (refs 2-4). Here we report the identification of a massive starburst galaxy at z = 6.34 through a submillimetre colour-selection technique. We unambiguously determined the redshift from a suite of molecular and atomic fine-structure cooling lines. These measurements reveal a hundred billion solar masses of highly excited, chemically evolved interstellar medium in this galaxy, which constitutes at least 40 per cent of the baryonic mass. A 'maximum starburst' converts the gas into stars at a rate more than 2,000 times that of the Milky Way, a rate among the highest observed at any epoch. Despite the overall downturn in cosmic star formation towards the highest redshifts, it seems that environments mature enough to form the most massive, intense starbursts existed at least as early as 880 million years after the Big Bang. [ABSTRACT FROM AUTHOR]

The possibility of detecting changes in the radial velocities of UX Ori stars during eclipses by circumstellar dust clouds is examined. Calculations show that, despite the large sizes of the clouds, this effect may actually be observable and, perhaps, has already been observed during spectral studies of stars of this kind. Monitoring of events of this kind can provide important information about the motion of matter in close proximity to young stars, as well as about the structure of gas-dust clouds shielding a star. [ABSTRACT FROM AUTHOR]

The propagation of Gardner solitons (GSs) in a nonplanar (cylindrical and spherical) geometry associated with a dusty plasma whose constituents are non-inertial negative static dust, inertial ions, and two population of Boltzmann electrons with two distinctive temperatures, are investigated by deriving the modified Gardner (mG) equation using the reductive perturbation method. The basic features of nonplanar dust-ion-acoustic GSs are analyzed by numerical solutions of mG equation. It has been found that the basic characteristics of GSs, which are shown to exist for the values of μ= n/ n around 0.319 for n/ n=0.04 and T/ T=0.2 [where n ( n) is the cold (hot) electron number density at equilibrium, T ( T) is the temperature of the cold (hot) electron species] are different from those of K-dV (Korteweg-de Vries) solitons, which do not exist around μ≃0.319. The implications of our results in understanding the nonlinear electrostatic perturbations observed in many laboratory and astrophysical situations (viz. double-plasma machines, rf discharge plasma, noctilucent cloud region in Earth's atmosphere, source regions of Auroral Kilometric Radiation, Saturn's E-ring, etc.) where electrons with different temperatures can significantly modify the wave dynamics, are also briefly discussed. [ABSTRACT FROM AUTHOR]

This paper investigates the motion of an infinitesimal body in the generalized restricted three-body problem. It is generalized in the sense that both primaries are radiating, oblate bodies, together with the effect of gravitational potential from a belt. It derives equations of the motion, locates positions of the equilibrium points and examines their linear stability. It has been found that, in addition to the usual five equilibrium points, there appear two new collinear points L, L due to the potential from the belt, and in the presence of all these perturbations, the equilibrium points L, L come nearer to the primaries; while L, L, L, L move towards the less massive primary and L moves away from it. The collinear equilibrium points remain unstable, while the triangular points are stable for 0< μ< μ and unstable for $\mu_{c} \le\mu\le\frac{1}{2}$, where μ is the critical mass ratio influenced by the oblateness and radiation of the primaries and potential from the belt, all of which have destabilizing tendency. A practical application of this model could be the study of the motion of a dust particle near the oblate, radiating binary stars systems surrounded by a belt. [ABSTRACT FROM AUTHOR]

Dust acoustic (DA) shock waves are investigated in a dusty plasma having a high-energy-tail electron distribution. The effects of ion streaming, charge variation and electron deviation from the Maxwellian distribution on the DA shock wave are then considered. It is shown that as the suprathermal character of the plasma is increased, the potential amplitude enhances. It is also found that the ion temperature may be destructive for the formation of DA shock waves. Their strength decreases with increasing ion streaming speed. Our results may be useful in understanding the basic nonlinear features of the DA wave propagation that may occur in space dusty plasmas, especially those including a relative motion between species (comet tails, solar wind streams, etc.). [ABSTRACT FROM AUTHOR]