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ExoKuiper belts around young A-type stars often host CO gas, whose origin is still unclear. The ALMA survey to Resolve exoKuiper belt Substructures (ARKS) includes 6 of these gas-bearing belts, to characterise their dust and gas distributions and investigate the gas origin. As part of ARKS, we observed the gas-rich system HD121617 and discovered an arc of enhanced dust density. In this paper, we analyse in detail the dust and gas distributions and the gas kinematics of this system. We extracted radial and azimuthal profiles of the dust (in the millimetre and near-infrared) and gas emission ($^{12}$CO and $^{13}$CO) from reconstructed images. To constrain the morphology of the arc, we fitted an asymmetric model to the dust emission. To characterise the gas kinematics, we fitted a Keplerian model to the velocity map and extracted the azimuthal velocity profile by deprojecting the data. We find that the dust arc is narrow (1-5 au wide at a radius of 75 au), azimuthally extended, and asymmetric; the emission is more azimuthally compact in the direction of the system's rotation, and represents 13% of the total dust mass (0.2$M_\oplus$). The arc is much less pronounced or absent for smal

Despite the implied presence of dust through reddened UV emission in high-redshift galaxies, no dust emission has been detected in the (sub)millimetre regime beyond $z > 8.3$. This study combines around two hundred hours of Atacama Large Millimeter/submillimeter Array (ALMA) and Northern Extended Millimeter Array (NOEMA) observations on ten $z > 8$ galaxies, revealing no significant dust emission down to a $1 σ$ depth of $2.0$, $2.0$, and $1.5 \,μ$Jy at rest-frame 158, 88 $μ$m, and across all the data, respectively. This constrains average dust masses to be below $< 10^{5}$ M$_{\odot}$ at $3 σ$ and dust-to-stellar mass ratios to be below $3.7 \times{} 10^{-4}$ (assuming $T_{\rm dust} = 50$ K and $β_{\rm dust} = 2.0$). Binning by redshift ($8 < z < 9.5$ and $9.5 < z < 15$), UV-continuum slope ($β_{\rm UV} \lessgtr -2$) and stellar mass ($\log_{10} M_{\ast}/{\rm M_{\odot}} \lessgtr 9$) yields similarly stringent constraints. Combined with other studies, these results are consistent with inefficient dust build-up in the $z > 8$ Universe, likely due to inefficient supernova production, limited interstellar grain growth and/or ejection by outflows. We provide dat

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. 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 w

Hot exozodiacal dust is dust in the innermost regions of planetary systems, at temperatures around 1000K to 2000K, and commonly detected by near-infrared interferometry. The phenomenon is poorly understood and has received renewed attention as a potential risk to a planned future space mission to image potentially habitable exoplanets and characterize their atmospheres (exo-Earth imaging) such as the Habitable Worlds Observatory (HWO). In this article, we review the current understanding of hot exozodiacal dust and its implications for HWO. We argue that the observational evidence suggests that the phenomenon is most likely real and indeed caused by hot dust, although conclusive proof in particular of the latter statement is still missing. Furthermore, we find that there exists as of yet no single model that is able to successfully explain the presence of the dust. We find that it is plausible and not unlikely that large amounts of hot exozodiacal dust in a system will critically limit the sensitivity of exo-Earth imaging observations around that star. It is thus crucial to better understood the phenomenon in order to be able to evaluate the actual impact on such a mission, and cur

We have recently suggested that dust growth in the cold gas phase dominates the dust abundance in elliptical galaxies while dust is efficiently destroyed in the hot X-ray emitting plasma (hot gas). In order to understand the dust evolution in elliptical galaxies, we construct a simple model that includes dust growth in the cold gas and dust destruction in the hot gas. We also take into account the effect of mass exchange between these two gas components induced by active galactic nucleus (AGN) feedback. We survey reasonable ranges of the relevant parameters in the model and find that AGN feedback cycles actually produce a variety in cold gas mass and dust-to-gas ratio. By comparing with an observational sample of nearby elliptical galaxies, we find that, although the dust-to-gas ratio varies by an order of magnitude in our model, the entire range of the observed dust-to-gas ratios is difficult to be reproduced under a single parameter set. Variation of the dust growth efficiency is the most probable solution to explain the large variety in dust-to-gas ratio of the observational sample. Therefore, dust growth can play a central role in creating the variation in dust-to-gas ratio thr

Exozodiacal dust disks (exozodis) are populations of warm (~300K) or hot (~1000K) dust, located in or interior to a star's habitable zone, detected around ~25% of main-sequence stars as excess emission over the stellar photosphere at mid- or near-infrared wavelengths. Often too plentiful to be explained by an in-situ planetesimal belt, exozodi dust is usually thought to be transported inwards from further out in the system. There is no consensus on which (if any) of various proposed dynamical models is correct, yet it is vital to understand exozodis given the risk they pose to direct imaging and characterisation of Earth-like planets. This article reviews current theoretical understanding of the origin and evolution of exozodi dust. It also identifies key questions pertinent to the potential for exozodis to impact exoplanet imaging and summarises current understanding of the answer to them informed by exozodi theory. These address how exozodi dust is delivered, its size and spatial distribution, and the effect of its composition on exozodi observability, as well as the connection between hot and warm exozodis. Also addressed are how common different exozodi levels are and how that

Interstellar dust plays decisive roles in the conversion of neutral to molecular hydrogen (H_2), the thermodynamical evolution of interstellar medium (ISM), and the modification of spectral energy distributions (SEDs) of galaxies. These important roles of dust have not been self-consistently included in previous numerical simulations of galaxy formation and evolution. We have therefore developed a new model by which one can investigate whether and how galaxy formation and evolution can be influenced by dust-related physical processes such as photo-electric heating, H_2 formation on dust, and stellar radiation pressure on dust in detail. A novel point of the model is that different dust species in a galaxy are represented by `live dust' particles (i.e., not test particles). Therefore, dust particles in a galaxy not only interact gravitationally with all four components of the galaxy (i.e., dark matter, stars, gas, and dust) but also are grown and destroyed through physical processes of ISM. First we describe a way to include dust-related physical processes in Nbody+hydrodynamical simulations of galaxy evolution in detail. Then we show some preliminary results of dust-regulated galax

We present dust features and masses observed in young supernova remnants (SNRs) with Spitzer IRS mapping and staring observations of four youngest supernova remnants: SNR 1E102.2-7219 (E0102) in the SMC, Cas A and G11.2-0.3 in our Galaxy, and N132D in the LMC. The spectral mapping data revealed a number of dust features which include 21 micron-peak dust and featureless dust in Cas A and 18-micron peak dust in E0102 and N132D. The 18 micron-peak feature is fitted by a mix of MgSiO$_3$ and solid Si dust grains, while the 21-micron peak dust is by a mix of silicates and FeO; we also explore dust fitting using Continuous Distribution of Ellipsoid grain models. We report detection of CO fundamental band from Cas A in near-infrared. We review dust features observed and identified in other SNRs. The dust emission is spatially correlated with the ejecta emission, showing dust is formed in SN ejecta. The spectra of E0102 show rich gas lines from ejecta including strong ejecta lines of Ne and O, including two [Ne III] lines and two [Ne V] lines which allow us to diagnostic density and temperature of the ejecta and measure the ejecta masses. E0102 and N132D show weak or lacking Ar, Si, and Fe

Interstellar dust grains do not have a single well-defined origin. Stars are demonstrably dust producers, but also efficient destroyers of cosmic dust. Dust destruction in the ISM is believed to be the result of SN shocks hitting the ambient ISM gas (and dust) and lead to an increased rate of ion sputtering, which reduces the dust mass. Grains located in cold molecular clouds can on the other hand grow by condensation, thus providing a replenishment mechanism or even a dominant channel of dust formation. In dense environments grains may coagulate and form large composite grains and aggregates and if grains collide with large enough energies they may be shattered, forming a range of smaller debris grains. The present paper presents a statistical modelling approach using the method of moments, which is computationally very inexpensive and may therefore be an attractive option when combining dust processing with, e.g., detailed simulations of interstellar gas dynamics. A solar-neighbourhood-like toy model of interstellar dust evolution is presented as an example.

Spacecraft investigations during the last ten years have vastly improved our knowledge about dust in the Jovian system. All Galilean satellites, and probably all smaller satellites as well, are sources of dust in the Jovian system. In-situ measurements with the dust detectors on board the Ulysses and Galileo spacecraft have for the first time demonstrated the electromagnetic interaction of charged dust grains with the interplanetary magnetic field and with a planetary magnetosphere. Jupiter's magnetosphere acts as a giant mass-velocity spectrometer for charged 10-nanometer dust grains. These dust grains are released from Jupiter's moon Io with typical rate of 1 kg s^1. The dust streams probe the plasma conditions in the Io plasma torus and can be used as a potential monitor of Io's volcanic plume activity. The other Galilean satellites are surrounded by tenuous impact-generated clouds of mostly sub-micrometer ejecta grains. Galileo measurements have demonstrated that impact-ejecta derived from hypervelocity impacts onto satellites are the major -- if not the only -- constituent of dusty planetary rings. We review the in-situ dust measurements at Jupiter and give an update of most r

A viable interstellar dust model - characterized by the composition, morphology, and size distribution of the dust grains and by the abundance of the different elements locked up in the dust - should fit all observational constraints arising primarily from the interactions of the dust with incident radiation or the ambient gas. In spite of the many different manifestations of these interactions, we still lack a comprehensive dust model that is consistent with {\it all} the observational constraints. An important advance towards the construction of such a model was recently made by Zubko, Dwek, and Arendt (2003, ZDA03) who, for the first time, included the average interstellar extinction, the diffuse infrared emission, {\it and} the interstellar abundances as explicit constraints in the construction of models consisting of astrophysical dust particles without any predetermined functional form for their grain size distribution. The results showed the existence of many distinct dust models that satisfy a basic set of observational constraints. X-ray halos, produced primarily by small angle scattering off large dust particles along the line of sight to bright X-ray sources, probe dust

Enhancing the local dust-to-gas ratio in protoplanetary discs is a necessary first step to planetesimal formation. In laminar discs, dust settling is an efficient mechanism to raise the dust-to-gas ratio at the disc midplane. However, turbulence, if present, can stir and lift dust particles, which ultimately hinders planetesimal formation. In this work, we study dust settling in protoplanetary discs with hydrodynamic turbulence sustained by the vertical shear instability. We perform axisymmetric numerical simulations to investigate the effect of turbulence, particle size, and solid abundance or metallicity on dust settling. We highlight the positive role of drag forces exerted onto the gas by the dust for settling to overcome the vertical shear instability. In typical disc models we find particles with a Stokes number $\sim 10^{-3}$ can sediment to $\lesssim 10\%$ of the gas scale-height, provided that $Σ_\mathrm{d}/Σ_\mathrm{g}\gtrsim 0.02$-$0.05$, where $Σ_\mathrm{d,g}$ are the surface densities in dust and gas, respectively. This coincides with the metallicity condition for small particles to undergo clumping via the streaming instability. Super-solar metallicities, at least loc

In this paper, the dynamical analysis of the Jovian dust originating from the four Galilean moons is presented. High accuracy orbital integrations of dust particles are used to determine their dynamical evolution. A variety of forces are taken into account, including the Lorentz force, solar radiation pressure, Poynting-Robertson drag, solar gravity, the satellites' gravity, plasma drag, and gravitational effects due to non-sphericity of Jupiter. More than 20,000 dust particles from each source moon in the size range from 0.05 micron to 1 cm are simulated over 8,000 (Earth) years until each dust grain hits a sink (moons, Jupiter, or escape from the system). Configurations of dust number density in the Jovicentric equatorial inertial frame are calculated and shown. In a Jovicentric frame rotating with the Sun the dust distributions are found to be asymmetric. For certain small particle sizes, the dust population is displaced towards the Sun, while for certain larger sizes, the dust population is displaced away from the Sun. The average lifetime as a function of particle size for ejecta from each source moon is derived, and two sharp jumps in the average lifetime are analyzed. Transp

Observations of neutral hydrogen (HI) and molecular gas show that 50% of all nearby early-type galaxies (ETGs) contain some cold gas. Molecular gas is always found in small gas discs in the central region of the galaxy, while neutral hydrogen is often distributed in a low-column density disc or ring typically extending well beyond the stellar body. Dust is frequently found in ETGs as well. The goal of our study is to understand the link between dust and cold gas in nearby ETGs as a function of HI content. We analyse deep optical $g-r$ images obtained with the MegaCam camera at the Canada-France-Hawaii Telescope for a sample of 21 HI-rich and 41 HI-poor ETGs. We find that all HI-rich galaxies contain dust seen as absorption. Moreover, in 57 percent of these HI-rich galaxies, the dust is distributed in a large-scale spiral pattern. Although the dust detection rate is relatively high in the HI-poor galaxies ($\sim$59 percent), most of these systems exhibit simpler dust morphologies without any evidence of spiral structures. We find that the HI-rich galaxies possess more complex dust morphology extending to almost two times larger radii than HI-poor objects. We measured the dust conten

In a previous paper we simulated the orbital evolution of dust particles from the Jupiter Trojan asteroids ejected by the impacts of interplanetary particles, and evaluated their overall configuration in the form of dust arcs. Here we compare the orbital properties of these Trojan dust particles and the Trojan asteroids. Both Trojan asteroids and most of the dust particles are trapped in the Jupiter 1:1 resonance. However, for dust particles, this resonance is modified because of the presence of solar radiation pressure, which reduces the peak value of the semi-major axis distribution. We find also that some particles can be trapped in the Saturn 1:1 resonance and higher order resonances with Jupiter. The distributions of the eccentricity, the longitude of pericenter, and the inclination for Trojans and the dust are compared. For the Trojan asteroids, the peak in the longitude of pericenter distribution is about 60 degrees larger than the longitude of pericenter of Jupiter; in contrast, for Trojan dust this difference is smaller than 60 degrees, and it decreases with decreasing grain size. For the Trojan asteroids and most of the Trojan dust, the Tisserand parameter is distributed

We present recent advances in theoretical studies of the formation and evolution of dust in primordial supernovae (SNe) that are considered to be the main sources of dust in the early universe. Being combined with the results of calculations of dust formation in the ejecta of Population III SNe, the investigations of the evolution of newly formed dust within supernova remnants (SNRs) show that smaller grains are predominantly destroyed by sputtering in the shocked gas, while larger grains are injected into the ambient medium. The mass of dust grains surviving the destruction in SNRs reaches up to 0.1--15 $M_\odot$, which is high enough to account for the content of dust observed for the host galaxies of quasars at $z > 5$. In addition, the transport of dust formed in the ejecta causes the formation of low-mass stars in the dense shell of primordial SNRs and affects the elemental composition of those stars. We also show that the flat extinction curve is expected in the high-redshift universe where SNe are the possible sources of dust.

We present a new technique to infer dust locations towards reddened Type Ia supernovae and to help discriminate between an interstellar and a circumstellar origin for the observed extinction. Using Monte Carlo simulations, we show that the time-evolution of the light-curve shape and especially of the colour excess \ebv~places strong constraints on the distance between dust and the supernova. We apply our approach to two highly-reddened Type Ia supernovae for which dust distance estimates are available in the literature: SN 2006X and SN 2014J. For the former, we obtain a time-variable $E(B-V)$ and from this derive a distance of $27.5^{+9.0}_{-4.9}$ or $22.1^{+6.0}_{-3.8}$ pc depending on whether dust properties typical of the Large Magellanic Cloud (LMC) or the Milky Way (MW) are used. For the latter, instead, we obtain a constant $E(B-V)$ consistent with dust at distances larger than 50 and 38 pc for LMC$-$ and MW$-$type dust, respectively. Values thus extracted are in excellent agreement with previous estimates for the two supernovae. Our findings suggest that dust responsible for the extinction towards these supernovae is likely to be located within interstellar clouds. We also d

Observational evidence seems to indicate that the depletion of interstellar carbon into dust shows rather wide variations and that carbon undergoes rather rapid recycling in the interstellar medium (ISM). Small hydrocarbon grains are processed in photo-dissociation regions by UV photons, by ion and electron collisions in interstellar shock waves and by cosmic rays. A significant fraction of hydrocarbon dust must therefore be re-formed by accretion in the dense, molecular ISM. A new dust model (Jones et al., Astron. Astrophys., 2013, 558, A62) shows that variations in the dust observables in the diffuse interstellar medium (nH = 1000 cm^3), can be explained by systematic and environmentally-driven changes in the small hydrocarbon grain population. Here we explore the consequences of gas-phase carbon accretion onto the surfaces of grains in the transition regions between the diffuse ISM and molecular clouds (e.g., Jones, Astron. Astrophys., 2013, 555, A39). We find that significant carbonaceous dust re-processing and/or mantle accretion can occur in the outer regions of molecular clouds and that this dust will have significantly different optical properties from the dust in the adjac

Mineral dust aerosols impact Earth's radiation budget through interactions with clouds, ecosystems, and radiation, which constitutes a substantial uncertainty in understanding past and predicting future climate changes. One of the causes of this large uncertainty is that the size distribution of emitted dust aerosols is poorly understood. The present study shows that regional and global circulation models (GCMs) overestimate the emitted fraction of clay aerosols (< 2 μm diameter) by a factor of ~2 - 8 relative to measurements. This discrepancy is resolved by deriving a simple theoretical expression of the emitted dust size distribution that is in excellent agreement with measurements. This expression is based on the physics of the scale-invariant fragmentation of brittle materials, which is shown to be applicable to dust emission. Because clay aerosols produce a strong radiative cooling, the overestimation of the clay fraction causes GCMs to also overestimate the radiative cooling of a given quantity of emitted dust. On local and regional scales, this affects the magnitude and possibly the sign of the dust radiative forcing, with implications for numerical weather forecasting an