We estimate the consequences of a potential strong decrease of the solar activity using the model simulations of the future driven by pure anthropogenic forcing as well as its combination with different solar activity related factors: total solar irradiance, spectral solar irradiance, energetic electron precipitation, solar protons and galactic cosmic rays. The comparison of the model simulations shows that introduced strong decrease of solar activity can lead to some delay of the ozone recovery and partially compensate greenhouse warming acting in the direction opposite to anthropogenic effects. The model results also show that all considered solar forcings are important in different atmospheric layers and geographical regions. However, in the global scale the solar irradiance variability can be considered as the most important solar forcing. The obtained results constitute probably the upper limit of the possible solar influence. Development of the better constrained set of future solar forcings is necessary to address the problem of future climate and ozone layer with more confidence.

Major photometric monitoring campaigns of star-forming regions in the past decade have provided rich rotation period distributions of pre-main-sequence stars. The rotation periods span more than an order of magnitude in period, with most falling between 1 and 10 days. Thus the broad rotation period distributions found in 100 Myr clusters are already established by an age of 1 Myr. The most rapidly rotating stars are within a factor of 2-3 of their critical velocities; if angular momentum is conserved as they evolve to the ZAMS, these stars may come to exceed their critical velocities. Extensive efforts have been made to find connections between stellar rotation and the presence of protostellar disks; at best only a weak correlation has been found in the largest samples. Magnetic disk-locking is a theoretically attractive mechanism for angular momentum evolution of young stars, but the links between theoretical predictions and observational evidence remain ambiguous. Detailed observational and theoretical studies of the magnetospheric environments will provide better insight into the processes of pre-main-sequence stellar angular momentum evolution.

We have obtained high-resolution spectra and carried out a detailed elemental abundance analysis for a new sample of 899 F and G dwarf stars in the Solar neighbourhood. The results allow us to, in a multi-dimensional space consisting of stellar ages, detailed elemental abundances, and full kinematic information for the stars, study and trace their respective origins. Here we briefly address selection criteria and discuss how to define a thick disc star. The results are discussed in the context of galaxy formation.

The prototype telescope and instruments for the Stellar Observations Network Group (SONG) are nearing completion at the Observatorio del Teide on Tenerife. In this contribution we describe the current status (autumn 2013) of the telescope and its instrumentation. Preliminary performance characteristics are presented for the high-resolution spectrograph based on daytime observations of the Sun and a 4 hour test series obtained for the sub-giant β Aquilae.

Recent observational and theoretical results are reviewed that pertain to the presence and characteristics of stellar coronae and winds in late-type stars. It is found that stars - principally dwarfs - exist with “hot” coronae similar to the Sun with thermally driven winds. For stars, at the lowest effective temperatures, and gravities characteristic of supergiant and giant stars, high temperature (~105K) atmospheres are absent (or if present are substantially weaker than in the dwarf stars), and massive winds are present. There also exist “hybrid” examples - luminous stars possessing both a “hot” corona and a supersonic stellar wind. Constraints for theoretical models are discussed.

The situation in terms of regulation of light pollution in Italy is here presented. The activity, started with the effort of amateur astronomers, lighting engineers and professional astronomers, is split into several actions oriented both to the local and national levels. One of the first goals was an ordinance of the city of Frosinone providing specific guidelines for lighting. The provinces of Valle d'Aosta and Veneto have followed up with local laws. The regional law of Valle d'Aosta includes a safeguard for nocturnal fauna from light pollution. The regional law of Veneto includes protection of the environment, observatories and astronomical sites. To avoid a proliferation of local laws, a national Italian bill was submitted and it is still under discussion. Bill No. 751 has been approved by the general assembly of the Italian Astronomical Society and provides more specific guidelines and standards concerning lighting in order to avoid unnecessary upward illumination and to reduce glare. At the same time a new technical standard, UNI 10819, has been settled after long debate among UNI (Italian National Standards Institute), the Italian Astronomical Society's Light Pollution Committee, lighting engineers and representatives of lighting manufacturers.

The superluminal knots of VLBI-sources are widely believed to be shocks travelling along relativistic jets. So far only very simple quasi-one dimensional models have been used to study this phenomenon. Recent progress in numerical methods for relativistic fluid dynamics (Falle & Komissarov 1995) make it possible to carry out much more realistic simulations of such flows.

We have tried to find empirical evidence for the role of photospheric motions in the building up of the flare productive magnetic patterns in Active Regions.

The bright Hα faculae are associated with V∥ structures different from a classical Evershed flow and particularly ‘anomalous’ in the regions and periods of high flare occurrence. The flares observed occurred at ‘crossings’ of the lines V∥ = 0(V ≠ 0) and H∥ = 0 and at places where V∥ = 0 showed abrupt changes of direction. It is suggested that these anomalous V∥ structures are evidence of vortex motions.

IRAS observations of the Galactic Center are presented. The maps at 12, 25, 60 and 100 μm have a typical resolution of a few arcmin and cover an area 6×2 deg2 centered on SgrA. All data have been corrected for the zodiacal light contamination and for the diffuse emission associated with the galactic disk. The infrared radiation originating in the Galactic Center arises from well-defined sources which can be identified with known radio sources and from an extended emission which accounts for most of the infrared luminosity. The total infrared luminosity associated with the Galactic Center (area 3°×2°) amounts to 109L⊙. The sources contribute 10% to this luminosity. A comparison with surveys in the radio continuum and in the near infrared is presented. Results are analyzed in terms of star formation history. In particular, it is suggested that the dominant heating source for the dust is the population of cool stars - K and M giants - comprising the galactic nucleus.

Stars like our Sun and planets like our Earth form in dense regions within interstellar molecular clouds, called pre-stellar cores (PSCs). PSCs provide the initial conditions in the process of star and planet formation. In the past 15 years, detailed observations of (low-mass) PSCs in nearby molecular cloud complexes have allowed us to find that they are cold (T < 10K) and quiescent (molecular line widths are close to thermal), with a chemistry profoundly affected by molecular freeze-out onto dust grains. In these conditions, deuterated molecules flourish, becoming the best tools to unveil the PSC physical and chemical structure. Despite their apparent simplicity, PSCs still offer puzzles to solve and they are far from being completely understood. For example, what is happening to the gas and dust in their nuclei (the future stellar cradles) is still a mystery that awaits for ALMA. Other important questions are: how do different environments and external conditions affect the PSC physical/chemical structure? Are PSCs in high-mass star forming regions similar to the well-known low-mass PSCs? Here I review observational and theoretical work on PSCs in nearby molecular cloud complexes and the ongoing search and study of massive PSCs embedded in infrared dark clouds (IRDCs), which host the initial conditions for stellar cluster and high-mass star formation.

A few of the questions proposed earlier to the contributors are reviewed to identify some of the unsolved problems related to the different interfaces between comets, asteroids, and meteorites and their evolution and origin.

We observed a total of 13 low-redshift AGN with the Hopkins Ultraviolet Telescope (HUT) during the course of the Astro-1 and Astro-2 missions. Of these, 4 show intrinsic Lyman-limit absorption — NGC 1068, NGC 4151, NGC 3516 and NGC 3227. AU galaxies with optically thick Lyman limits have extended narrow-line regions with bi-polar morphologies. All AGN with no absorption are Seyfert Is with compact NLRs. These observations support geometrical shadowing as the means for collimating the ionizing radiation in unified models of AGN, most likely in a photoionized atmosphere above the obscuring torus.

Using the many-body techniques appropriate for quantum crystals it is shown that the deep interior of a neutron star is most likely an orderly arrangement of neutrons, protons and hyperons forming a solid. It is shown that a liquid or gas arrangement would produce higher energy. If so, a neutron star can be viewed as two solids (crust and core) permeated by a layer of ordinary or (perhaps) superfluid liquid. Astronomical evidence is in favor of such a structure: the sudden jumps in the periods of the Crab and Vela pulsars that differ by a factor of ∼ 102 can be easily explained by the star-quake model. If the Crab is less massive than Vela (i.e., if it is not dense enough to have a solid core), the star-quakes take place in the crust whereas for Vela they occur in the core.

On 1957 November 4, an unprecedented solar radio event was observed at meter wavelengths. Observations at 169 Mc/s were obtained by the Nançay Observatory (great interferometer and simple radio telescope) and by the Humain Observatory. At 200 Mc/s the event was observed by the Nera Observatory.

Plasma ejections and waves in the solar corona are almost exclusively flare associated phenomena. Ejections of relatively cool and dense plasma are frequently observed in Hα whereas observations in coronal light (visible, EUV- and X-radiation) are still rather scarce. Occurrence of coronal waves is so far best known from their effects on the Hα chromosphere and, of course, from the production of radio bursts. Only in relatively few cases have observations been made in coronal lines and in coronal continuum by ground based as well as by satellite borne equipment. We may expect, however, that the white light coronagraph and the X-ray telescopes on board of the Skylab will detect quite a number of events in front of the solar disk and high in the solar corona and will considerably increase and improve our imperfect knowledge and understanding of coronal ejections and waves as it is presented in this review.

Although the HST GSC–I (Paper-I: Lasker et al. 1990, Paper-II: Russell et al. 1990, Paper-III: Jenkner et al. 1990) has been used with great success operationally, it was always known that it was possible to improve the scientific and operational usefulness by an increase in scope to include multi-color and multi-epoch data. Once the GSC-II concept was established, it was evident that, even beyond the original motivations in HST operations, it would address a number of other astronomical needs such as increasing demands for fainter catalogues to support remote or queue scheduling capabilities and adaptive optics on the next generation of large-aperture, new-technology telescopes. In addition, the all sky nature of the GSC–II makes it a natural data source for research in galactic structure.

Attention is drawn to the fact that neither astronomical observations, nor laboratory data can, as yet, sufficiently constrain models of the origin and evolution of the solar system. But, if correctly approached and interpreted, the magnetic remanence of meteorites could help in constructing a self-consistent model.

In the context of various models for the early evolution of a solar nebula, the possible roles assigned to ambient magnetic fields and the paleointensities required to establish the stable natural remanent magnetization (NRM in range 10-4 to 10-1 cgsm) observed in meteorites, are discussed. It is suggested that the record of paleofields present during condensation, growth, and accumulation of grains is likely to have been preserved as chemical (CRM) or thermochemical (TCRM) remanence in unaltered meteoritic material. This interpretation of the meteoritic NRM is made plausible by experimental and theoretical results from the contiguous fields of rock magnetism, magnetic materials, interstellar grains, etc. Several arguments (such as the anisotropy of susceptibility in chondrites, suggesting alignment of elongated ferromagnetic grains, or the characteristic sizes and morphology of carrier phases of remanence, etc.) as well as general evidence from meteoritics (cooling rates, chemical and mineralogical data) can be used to challenge the interpretation of NRM as thermo-remanence (TRM) acquired on a “planetary” parent body during cooling of magnetic mineral phases through the Curie point in fields of 0.2 to 0.9 Oe.

Fine-particle theories appear adequate for treating meteoritic remanence, if models based on corresponding types of permanent magnet materials, e.g., powder-ferrites for chondrites; diffusion hardened alloys for iron meteorites, are adopted, as suggested here.

Finally, a potentially fruitful sequence of experiments is suggested for separating the useful component of NRM in determining the paleofield intensity and its time evolution.

Direct detection and spectral characterization of extrasolar planets is one of the most exciting but also one of the most challenging area in modern astronomy. For its second generation instrumentation on the VLT, ESO has supported two phase A studies for a so-called “Planet Finder” dedicated instrument. Based on the results of these two studies, a unique instrument is now considered for first light in early 2010, including a powerful extreme adaptive optics system, various coronagraphs, an infrared differential imaging camera, an infrared integral field spectrograph and a visible differential polarimeter. We will briefly summarize the science objectives and requirements, describe the proposed conceptual design and discuss the main limitations and corresponding instrumental issues of such a system. We will also derive the expected performance of the proposed Planet Finder and present the project organization.

We present the results of photometric and high-resolution spectroscopic studies of a group of B[e] stars (Be stars with warm dust or B[e]Ds) and of two cooler objects with extremely high luminosities (HDE 331319 and IRC+10420). The B[e]Ds is a growing group of objects with very strong emission-line spectra, some of which show direct evidence of the presence of a hot and a cool star in the system. Their basic properties and connection to other groups of binaries are discussed, and a new list of members is presented. Fundamental parameters and chemical composition of an unusual F-supergiant HDE 331319 and recent results on a fast evolving object IRC+10420 are also reported.

Globular cluster stars exhibit abundance anomalies which are not shared by their field counterparts. Two global scenarii have been proposed in the past to explain these differences: The primordial enrichment scenario and the evolutionary (or intrinsic) one. Recent observations well below the bump luminosity in globular clusters have raised the weight of the primordial solution. However the stellar sources responsible for these abundance variations have not yet been indubitably identified. In this review we discuss the possible stellar culprits as well as their pros and cons.