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Nearby galaxies are particularly relevant laboratories to study dust evolution due to the diversity of physical conditions they harbor and to the wealth of data at our disposal. In this paper, we review several recent advances in this field, mainly based on Herschel observations. We first discuss the problems linked with our ignorance of grain emissivities, and show that it can be constrained in some cases. New models are starting to incorporate these constraints. We then present methodological issues encountered when fitting spectral energy distributions, leading to biases in derived dust properties, and some attempts to solve them. Subsequently, we review studies scrutinizing dust evolution: (i) from a global point of view, inferring long term cosmic dust evolution; (ii) from a local point of view, looking for indices of dust processing in the ISM.

The process of the rapid origin of life on Earth is analyzed, taking into account the evolution of our Sun (the beginning of thermonuclear reactions). Given the knowledge about DNA, viruses and the structure of bacteria, it is concluded that the origin of life on Earth was initiated from the outside. Further, using space chemistry, it is shown that spontaneous assembly of DNA/RNA molecules can occur on particles of interstellar and intergalactic dust. Therefore, when favorable conditions are created on the planet, the emergence of life begins rapidly, since the initiators of life are already available from cosmic dust (RNA and DNA molecules).

This article is based on an invited talk given by V. P. Kulkarni at the 8th Cosmic Dust meeting. Dust has a profound effect on the physics and chemistry of the interstellar gas in galaxies and on the appearance of galaxies. Understanding the cosmic evolution of dust with time is therefore crucial for understanding the evolution of galaxies. Despite the importance of interstellar dust, very little is known about its nature and composition in distant galaxies. We summarize the results of our ongoing programs using observations of distant quasars to obtain better constraints on dust grains in foreground galaxies that happen to lie along the quasar sightlines. These observations consist of a combination of mid-infrared data obtained with the Spitzer Space Telescope and optical/UV data obtained with ground-based telescopes and/or the Hubble Space Telescope. The mid-IR data target the 10 $\mu$m and 18 $\mu$m silicate absorption features, while the optical/UV data allow determinations of element depletions, extinction curves, 2175 {\AA} bumps, etc. Measurements of such properties in absorption-selected galaxies with redshifts ranging from $z\sim0$ to $z>2$ provide constraints on the evolution of interstellar dust over the past $> 10$ Gyr. The optical depth of the 10 $\mu$m silicate absorption feature ($\tau_{10}$) in these galaxies is correlated with the amount of reddening along the sightline. But there are indications [e.g., based on the $\tau_{10}$ /$E(B-V)$ ratio and possible grain crystallinity] that the dust in these distant galaxies differs in structure and composition from the dust in the Milky Way and the Magellanic Clouds. We briefly discuss the implications of these results for the evolution of galaxies and their star formation history., Comment: 27 pages, including 5 figures. Accepted for publication in Planetary and Space Science

This special issue is primarily devoted to the 6th meeting on Cosmic Dust ( Cosmic Dust VI ), which was held at CPS (Center for Planetary Science) in Kobe, Japan, on August 5–9, 2013. This meeting was coordinated in an order where a friendly and welcoming atmosphere persuaded the participants of the meeting to develop human relations and interactions among themselves. This has been our interdisciplinary approach to answering the question of where dust comes from and where dust goes. We briefly review some of the exciting papers presented at the meeting and provide perspectives for the development of cosmic dust research.

We present results of optical broad-band and narrow-band Halpha observations of a sample of forty nearby early-type galaxies. The majority of sample galaxies are known to have dust in various forms viz. dust lanes, nuclear dust and patchy/filamentary dust. A detailed study of dust was performed for 12 galaxies with prominent dust features. The extinction curves for these galaxies run parallel to the Galactic extinction curve, implying that the properties of dust in these galaxies are similar to those of the Milky-Way. The ratio of total to selective extinction (Rv) varies between 2.1 and 3.8, with an average of 2.9 +/- 0.2, fairly close to its canonical value of 3.1 for our Galaxy. The average relative grain size /a_Gal of dust particles in these galaxies turns out to be 1.01 +/- 0.2, while dust mass estimated using optical extinction lies in the range 10^2 to 10^4 M(sun) . The Halpha emission was detected in 23 out of 29 galaxies imaged through narrow- band filters with the Halpha luminosities in the range 10^38 - 10^41 erg s^-1. The mass of the ionized gas is in the range 10^3-10^5 M(sun). The morphology and extent of ionized gas is found similar to those of dust, indicating possible coexistence of dust and ionized gas in these galaxies. The absence of any apparent correlation between blue luminosity and normalized IRAS dust mass is suggestive of merger related origin of dust and gas in these galaxies., Comment: 28 pages, 6 figures; Accepted for publication in New Astronomy. Please cite this article in press as: Kulkarni, S., et al. New Astron. (2014), http://dx.doi.org/10.1016/j.newast.2014.01.003

We present the results based on multiwavelength imaging observations of the prominent dust lane starburst galaxy NGC 1482 aimed to investigate the extinction properties of dust existing in the extreme environment. (B-V) colour-index map derived for the starburst galaxy NGC 1482 confirms two prominent dust lanes running along its optical major axis and are found to extend up to \sim 11 kpc. In addition to the main lanes, several filamentary structures of dust originating from the central starburst are also evident. Though, the dust is surrounded by exotic environment, the average extinction curve derived for this target galaxy is compatible with the Galactic curve, with RV =3.05, and imply that the dust grains responsible for the optical extinction in the target galaxy are not really different than the canonical grains in the Milky Way. Our estimate of total dust content of NGC 1482 assuming screening effect of dust is \sim 2.7 \times 10^5 Msun, and provide lower limit due to the fact that our method is not sensitive to the intermix component of dust. Comparison of the observed dust in the galaxy with that supplied by the SNe to the ISM, imply that this supply is not sufficient to account for the observed dust and hence point towards the origin of dust in this galaxy through a merger like event. Our multiband imaging analysis reveals a qualitative physical correspondence between the morphologies of the dust and H{\alpha} emission lines as well as diffuse X-ray emission in this galaxy. continue.... for more detail please see in pdf file., Comment: 22 pages, 11 Figures. Accepted for publication in New Astronomy

High-resolution two-dimensional magnetohydrodynamical simulations have been carried out to investigate the role of continuing infall of clumpy gas as a driver of turbulence in extended H i galactic discs. We have compared the responses of isothermal gas discs with sound speeds 4 and 8 km/s to infalling, condensed clouds. For mass accretion rates of ∼0.6 M ⊙ yr −1 , the turbulent motions in the outer disc become slightly faster than transonic. We suggest that the rain of compact high velocity clouds on the disc not only can fuel the Milky Way with fresh material but is a potential source of random motions in outer regions of H i discs.

Due to the gravitational force, clouds of dust and gas in the interstellar medium can contract and form stars and planet systems. Here we show that if the dust grains are electrically charged then the self-gravitation can be balanced by the “electrostatic pressure” and the collapse can be halted. In this case, the dust cloud may form soft dust planets, having the weight of a small moon or satellite, but a radius larger than of our Sun. There exist a critical mass beyond which the dust cloud collapses and forms a solid planet. We here present a simple model for the dynamics and equilibrium of self-gravitating dust clouds and apply the model to typical parameters for dust in molecular clouds and in the interstellar medium.

The question `Are supernovae important sources of dust?' is a contentious one. Condensation theory and observations of dust at very high redshifts suggests that they should be, since only massive stars evolve quickly enough to produce the large quantities of dust seen at such early times in the Universe. However, observations with IRAS and ISO have only detected very small amounts of hot dust in supernova remnants, not enough to make them significant sources of dust. Here, we present new observations of two young Galactic remnants with SCUBA, and show that large quantities of dust are indeed produced by supernovae.

The X-ray background intensity around galaxies and rich clusters of galaxies is investigated in three energy bands using the ROSAT All-Sky Survey maps. It is found that an amplitude of the XRB enhancements surrounding the Abell clusters and high density areas in the Lick galaxy counts depends on photon energy. Excess flux generated in the surrounding of the galaxy concentrations is consistent with the thermal emission by hot gas postulated by hydrodynamic simulations.

In the last few years, new instruments have allowed astronomers to measure the ratio of deuterium to hydrogen in intergalactic gas clouds at high redshift. The abundances of heavy elements in these clouds show directly that little processing of gas through stars has occurred. Therefore, the measurements are thought to represent a direct sampling of the deuterium abundance produced in the Big Bang. The numbers are not consistent with expectations, in that the values are not constant across different sightlines and in that the mean is not much higher than the Galactic [D/H] values. The latter were expected to be lower than intergalactic values of [D/H] by at least a factor of two because the primordial gas has been turned into stars, producing heavy elements but burning deuterium. Here, I explore the sources of systematic errors that might be underestimated in the analysis.

The astrophysical aspects of the evolutionary path from dust to planets have been known for a long time but it was only recently that it could be followed by astronomical observations (Hubble Space Telescope). It was also recently that the mineral and chemical properties of dust around young starsqu in different stage of stellar evolution could be determined (the Infrared Space Observatory). Dust around these stars, including Vega-type stars that serve as an analog for the solar nebula, was identified as pure Mg-silicates (forsteriteenstatite), Fe-bearing and pure-Fe amorphous ‘silicates’, silica, Fe-metal, Fe-oxides (possibly Fe-sulfides) amorphous carbon and polycyclic aromatic hydrocarbons. They are the same phases that make up the aggregate and cluster interplanetary dust particles (IDPs) collected in the lower stratosphere. Recent vapor phase condensation experiments showed that the original condensates were mostly amorphous, chemically ordered, metastable eutectic ‘FeSiO’, ‘MgSiO’and ferromagnesiosilica ‘silicate’dust from which the observed non-carbon mineralogy could have evolved during hierarchical dust accretion in the solar nebula. The hypothesis of hierarchical dust accretion uses the size distributions for the surprisingly limited number of non-chondritic dust types in aggregate and cluster IDPs as a measure of relative time. It predicts the accretion of gradually larger, relatively younger, dust aggregates with increasingly diverse chemical and mineral properties of increasingly larger crystalline grains that evolved from initially mostly amorphous dust. This early chemical and mineral dust evolution can be traced in the collected aggregate and in larger cluster IDPs and in even larger aggregate meteoroids that burn up during atmospheric entry flash-heating but whereof the resulting meteors contain information on the chemistry, grain size and texture of the original dust. These aggregate particles were protected against post-accretion, thermal or aqueous dust modification of the original presolar dust and the evolved mineralogy and chemistry during cold-storage inside icy protoplanets such as comet nuclei. The interplanetary dust particles provide ground truth to the properties and modification of the presolar dust in dense molecular clouds wherein stars, such as our sun, were born.

We use ROSAT/ASCA X-ray spectra of high-redshift AGNs to study the intergalactic medium in the deep Universe. Because the primordial gas is likely completely ionized but not the intergalactic metals, some soft X-ray absorption features are therefore expected to be detected in the spectra of distant AGNs. We have calculated the ionization state of a metal-rich IGM, and applied the model to the joint ASCA-ROSAT X-ray spectral analysis of four AGNs at redshifts ranging from 1.8 and up to nearly 5. This test provides a constraint on the temperature and density of the IGM, which gives a well consistent picture of the physical properties of the IGM, in comparison with the results obtained from the traditional Gunn-Peterson test, and constraints given by both the cosmic microwave background and the X-ray background.

The signature of objects in the very early universe lies deep in the near infrared bands. The Primordial Explorer ( PRIME ) is a proposed NASA Explorer-class mission aimed at the z > 10 universe. PRIME will find the youngest and the most luminous galaxies and quasars, thereby enabling the determination of the epoch of galaxy formation and that of reionization of the intergalactic medium.

Interstellar dust models, previously constrained only from the extinction curve, have been radically changed with the arrival of IRAS observations of the dust infrared emission. An important component of interstellar dust is likely to be made of small particles that show a fluctuating temperature upon impinging single photons and which can produce large near and mid infrared excesses ubiquitously observed in the Galaxy and external galaxies. The analysis of COBE data should soon improve our understanding of dust infrared emissivity and particularly for big grains in the submillimeter domain. We will discuss the key observations (spectral features, broad-band colors, correlations with gas tracers...) which put the best constraints on any dust models and show that the next generation of IR/submm satellites (ISO, SIRTF...) should improve our knowledge of interstellar dust composition and the dust redistribution of the stellar energy inside galaxies.

We propose to use the dust scattered X-ray halo of the quasar 3C273 to check the existence of an intergalactic dust component placed along the line of sight in an intergalactic cloud. Based on numerical models we point out that the intensity profile of the X-ray halo could enable to set constraints on the the galactic extinction along the line of sight, the contribution of extragalactic dust to the observed halo as well as its distribution between the X-ray source and the observer.

We review the results of an X-ray (ASCA) survey of intergalactic medium metallicities in 33 groups and clusters of galaxies. The observed picture could be explained either by adopting top heavy IMF for galaxies observed at high environment overdensities or by metal - rich SN II driven winds.

Assumptions of a tepid Universe and a smaller primordial contribution to the 3 K background are made to show that Pop III stars may be responsible for the 3 K background and cosmic ray entropy. The 3 K background would be caused by thermalized stellar radiation produced by metallized intergalactic dust formed in first generation stars. A range of mass scales and amplification factors of density perturbations in the early Universe is examined below the Jeans mass for gravitational instabilities. The density perturbations that could have been present at small enough mass scales could have survived and generated sonic modes that propagated through the plasma era and, when combined with additional gravitationally unstable entropy disturbances after recombination, triggered the formation of Pop III stars. 13 references.

It is shown that if the dust is present in the hot intergalactic gas, the galaxy cluster must be very bright source of far infrared emission. This emission can be observed by modern IR astronomy methods. At the same time, taking realistic assumptions about the intergalactic dust nature, it is impossible to explain negative results of the attempts made at observational detecting the Sunyaev-Zel'dovich effect in the centimeter wavelength region as the compensation of the expected decrements by the dust grains emission.