In this paper, we will review recent progress made in the understanding of cosmic silicates and the experimental characterization of relevant analogue materials. We will introduce the main structural properties of silicates. Then we will discuss recent infrared observations with a special emphasis on protoplanetary disks and AGNs. In the experimental section we will describe the optical properties of silicate grains. Here we will concentrate on fundamental optical data and the dependence of the optical behavior on particle shape and temperature.

We continued our search for partial (incomplete) Dyson spheres associated with solar-type stars (spectral types F, G and K) within 25 pc of the Sun. No candidate objects were found in a total of 384 stars.

On 13 December 2012, Chang'e-2 completed a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 meters from the asteroid's surface. The observations show that Toutatis has an irregular surface and its shape resembles a ginger-root of a smaller lobe (head) and a larger lobe (body). Such bilobate shape is indicative of a contact binary origin for Toutatis. In addition, the high-resolution images better than 3 meters provide a number of new discoveries about this asteroid, such as an 800-meter depression at the end of the large lobe, a sharply perpendicular silhouette near the neck region, boulders, indicating that Toutatis is probably a rubble-pile asteroid. Chang'e-2 observations have significantly revealed new insights into the geological features and the formation and evolution of this asteroid. In final, we brief the future Chinese asteroid mission concept.

The growth of urban development and its accompanying outdoor lighting has made the search for new observatory sites increasingly difficult. A method of predicting the brightness of the night sky produced by a city of known population and distance is useful in making studies of prospective new observatory sites, as well as in studying the likely future deterioration of existing sites. Other sources of light pollution can be investigated using the same model. In most cases, several cities are responsible for the light pollution at a given site, and the predicted night sky brightness is the sum of the contributions of all the cities. In this paper, we shall review the surprisingly little work which has been done on predicting night sky brightnesses from model calculations.

Detailed spectroscopic work has begun for several stars that have been classified WN 7. All show absorption lines in the upper Balmer series and in ionized helium. The absolute magnitudes, established from cluster membership, are relatively brighter than those of most other WR stars. In this paper the outflow velocity near the stellar photosphere is shown to be similar to that in Of stars. These WN 7 stars show somewhat larger emission line widths and probably have less hydrogen in their envelopes, but otherwise have similar luminosities and temperatures as Of stars.

Pollux is considered as an archetype of a giant star hosting a planet: its radial velocity (RV) presents sinusoidal variations with a period of about 590 d, which have been stable for more than 25 years. Using ESPaDOnS and Narval we have detected a weak (sub-gauss) magnetic field at the surface of Pollux and followed up its variations with Narval during 4.25 years, i.e. more than for two periods of the RV variations. The longitudinal magnetic field is found to vary with a sinusoidal behaviour with a period close to that of the RV variations and with a small shift in phase. We then performed a Zeeman Doppler imaging (ZDI) investigation from the Stokes V and Stokes I least-squares deconvolution (LSD) profiles. A rotational period is determined, which is consistent with the period of variations of the RV. The magnetic topology is found to be mainly poloidal and this component almost purely dipolar. The mean strength of the surface magnetic field is about 0.7 G. As an alternative to the scenario in which Pollux hosts a close-in exoplanet, we suggest that the magnetic dipole of Pollux can be associated with two temperature and macroturbulent velocity spots which could be sufficient to produce the RV variations. We finally investigate the scenarii of the origin of the magnetic field which could explain the observed properties of Pollux.

We present a new nutation series for the Earth (ZMOA-1990) based on (1) the rigid Earth nutation series developed by Zhu and Groten [1989], (2) the normalized response for an elastic, elliptical Earth with fluid-outer and solid-inner cores developed by Mathews et al. [1990], and (3) corrections for the effects of ocean tides and anelasticity, computed to be consistent with the Mathews et al. [1990] normalized response function. In deriving this series, only two parameters of the geophysical model for the Earth have been modified from their values computed with PREM: the dynamic ellipticities of the whole Earth, e, and of the fluid outer core, ef. The adopted values for these parameters, determined from the analysts of very long baseline interferometry (VLSI) data, are e=0.00328915 which is about 1% higher than the value obtained from PREM and 6×10−5 times larger than the IAU adopted value, and ef=0.002665 which is 4.6% higher than the PREM value. The above values were obtained from an adjustment of −0.3 ʺ/cent to the IAU-1976 luni-solar precession constant for e, and from the amplitude of the retrograde annual nutation for ef. The ZMOA-1990 nutation series agrees with estimates of the in-phase and the out-of-phase nutation amplitudes obtained from VLBI data to within 0.5 mas for the terms with 18.6 year period, and to better than 0.1 mas for terms at all other periods except for the out-of-phase terms with annual period (differences 0.39 mas, retrograde, and 0.13 mas, prograde), and for the in-phase term with prograde 13.66 day period (difference −0.25 mas).

This review describes work on the evolution of a stellar system during the phase which starts at the end of core collapse. It begins with an account of the models of Hénon, Goodman, and Inagaki and Lynden-Bell, as well as evaporative models, and modifications to these models which are needed in the core. Next, these models are related to more detailed numerical calculations of gaseous models, Fokker-Planck models, N-body calculations, etc., and some problems for further work in these directions are outlined. The review concludes with a discussion of the relation between theoretical models and observations of the surface density profiles and statistics of actual globular clusters.

An inner-truncated disk (ITD) brightness profile is one in which the inward extrapolation of the outer disk surface brightness significantly exceeds the observed surface brightness in a region near the galaxy center. Freeman (1970) identified these profiles as Type II profiles. Fourteen of Freeman’s (1970) sample of 36 external galaxies are designated as Type II (ITD); seven of the ITD’s are classified as barred galaxies and ITD’s are found at all morphological types.

Ohta, Hamabe, & Wakamatsu (1990) report that luminosity profiles perpendicular to the bars of six early-type galaxies all exhibit the Freeman Type II shape, while the feature is lost when azimuthally averaged profiles of the same galaxies are studied. They postulate that the bar formation resulted in an azimuthal redistribution of the stars, but no net radial redistribution.

We present a progress report on our ongoing HST WFPC2 study of globular clusters in NGC 185 and NGC 205. Most of the cluster candidates studied previously only from the ground are indeed globular clusters; however, several candidates turn out to be either foreground stars or background galaxies. In addition, we have discovered one new, previously unsuspected cluster. A complete knowledge of the globular cluster systems in even these nearby galaxies requires high spatial resolution data. We then derive preliminary I, (V – I) color-magnitude diagrams for some of the clusters, as well as for their surrounding fields. The clusters show the blue horizontal branches expected for the low metallicities we derive, which are in agreement with those derived from ground-based integrated spectra. The fields appear generally more metal-rich than indicated by previous ground-based studies. The field blue horizontal branch in NGC 185 is only a very minor component, while that in NGC 205 is even smaller. After all of our observations have been acquired, these data will allow a very accurate knowledge of the individual and composite properties of the globular cluster systems of these 2 galaxies, as well as those of their field stars.

As there are so many Australian Aboriginal and Torres Strait astronomies and cosmologies, commonalities are unusual. However one of the ‘things belonging to the sky’ that seems common to all groups across the continent is the open star cluster of the Pleiades. Yet interpretations of this cluster vary. So far I have tentatively identified four different cultural areas, the first being most of mainland Australia; the second being the islands south of mainland Australia known as Tasmania; the third being the cultural area of north-eastern Arnhem Land; and the fourth being the cultural area of the Torres Strait Islands. Within these areas, versions of the stories vary as contemporary circumstances change.

The cosmic abundance of the 3He isotope has important implications for many fields of astrophysics. We are using the 8.665 GHz hyperfine transition of 3He+ to determine the 3He/H abundance in Milky Way H ii regions and planetary nebulae. Here we review the 30 year history of our 3He program, report on its current status, and describe our future plans.

Deep convective envelopes of the red supergiants with masses smaller than 4 M⊙ are found to be dynamically unstable for the luminosities in the range of 4 × 103–5 × 104L⊙. The total energy of the envelopes is positive when the recombination energy of the ionized hydrogen and helium is taken into account, and is sufficient to expel a typical envelope up to infinite distance at a speed of 30 km/sec. We suggest that planetary nebulae are formed in this way.

We present in the following some capabilities of the Gaia mission for performing local test of General Relativity (GR) based on the astrometry of asteroids. This ESA cornerstone mission, to be launched in Spring 2012, will observe—in addition to the stars and QSOs—a large number of small solar system bodies with unprecedented photometric and, mostly, astrometric precisions. Indeed, it is expected that about 250,000 asteroids will be observed with a nominal precision ranging from a few milli-arcsecond (mas), to sub-mas precision, depending on the target's brightness. While the majority of this sample is constituted of known main-belt asteroids orbiting between Mars and Jupiter, a substantial fraction will be made of near-Earth objects, and possibly some newly discovered inner-Earth or co-orbital objects.

Here we show the results obtained from a simulation of Gaia observations for local tests of GR in the gravitational field of the Sun. The simulation takes into account the time sequences and geometry of the observations that are particular to Gaia observations of solar system objects, as well as the instrument sensitivity and photon noise. We show the results from a variance analysis for the nominal precision of the joint determination of the solar quadrupole J2 and the PPN parameter β. Additionally we include the link of the dynamical reference frame to the conventional kinematically non-rotating reference frame (as obtained in the visible wavelength by Gaia observations of QSOs). The study is completed by the determination of a possible variation of the gravitational constant /G, and deviation from Newtonian 1/r2 gravitational law. Comparisons to the results obtained from other techniques are also given.

We trace the history of observational solar prominence research from the early period when total solar eclipses provided the only means of observation, via the introduction of photography and spectroscopy in the 1860’s, to the present epoch when application of the Zeeman and the Hanle effects makes possible determination of the all-important magnetic fields in prominences.

Dividing prominence models into two classes, those that treat the support of the prominence against gravity and those concerned with the physical conditions in the prominence plasma itself, we describe the progress made in both classes of models since the 1950’s, when the first models were proposed. Finally, we comment on the necessity of combining aspects of the two classes of prominence models into a comprehensive picture that can account for the global nature of prominence support and stability, and where the adjacent coronal structures play an important role.

The apparent radial velocity of a star, as deduced from wavelength shifts, comprises not merely its true velocity, but also components arising from dynamics in the star’s atmosphere, gravitational redshift, and other effects. For the Sun, such phenomena can be segregated since the relative Sun-Earth motion is known from planetary system dynamics. This is now becoming possible also for other stars, whose true radial motions are determined through space astrometry. A study of the differences between accurate astrometric velocities (from Hipparcos), and precise spectroscopic values (from ELODIE) is in progress. Data for cool stars in the Hyades indicate a tendency of relative blueshifts among earlier main-sequence F-type stars, and in giants. This is theoretically expected: an increased convective blueshift due to the more vigorous convection in F-stars, and a decreased gravitational redshift in giants.

There are a lot of records concerning ancient Guest Stars (AGS) in Chinese historical books. Two catalogues of ancient nova or supernova were compiled (Xi 1955, Xi and Bo 1965, 1966) that listed 90 probable nova or supernova observed between 14 BC and 17 AD. The identify of AD. 1054 Guest star with Crab Nebula proved that the historical records are valuable to astrophysics. Since the discovery of the Crab pulsar in 1967, much attention has been paid to the relation between AGS and supernova remnants (SNR). Eight pairs of identification were suggested by Clark and Stephenson (1977). The number of SNR identified is two few to compare with the expectation from the frequency of supernova. In fact a lot of SNR or AGS have not been identified. It seems necessary, important and possible to look for further identification.

Most stars in our Galaxy with photospheric C/O > 1 (carbon stars) are not giants but dwarfs. The newly-recognized class of dwarf carbon stars joins the growing family of stars with peculiar abundances that are now recognized as products of mass-transfer binary (MTB) evolution. The dozen examples now known span a wide range of evolutionary histories, ages, and abundances. These stars can already provide some much-needed constraints on the formation of AGB C stars in the disk and spheroid populations, and on the parameters characterizing binary evolution there. A larger sample, with some bright members, would hasten our progress.

Various physical processes are believed to trigger star formation on the borders of Galactic HII regions. Among these, the collect & collapse process is particularly attractive as it allows the formation of massive objects (single stars or clusters). In order to identify specific cases of this way of triggering star formation we are carrying out a multi-wavelength study of Galactic HII regions that exhibit signposts of massive-star formation at their borders. Hereby, we present two typical examples of such sources and discuss the results in the framework of the collect and collapse process, which seems to be at work as the major triggering agent in these two cases.