The first site testing campaigns started at Dome C during the summer season 2000–2001. Since then, each further summer has been exploited, as well as the first three winter seasons permitted by the opening of the Concordia station in 2005. Many of the astronomical site properties begin now to be well known, although some more still need to be adressed and more statistics is obviously required.

In its first part, this paper summarizes recent work on the mass andshape of the Galactic dark halo. The second part presents a review ofthe large-scale structure of the Milky Way, and of the evidence thatthe inner Galaxy is dominated by baryonic matter. This is brieflycompared with the predictions of ΛCDM and MOND. Finally, asummary is given of bulge formation from clumpy, gas-rich disks, aprocess which may give rise to old, disk-like, α-rich bulgessimilar to the Galactic bulge.

Extensive simulations of planetary transits in the epoch photometry of the future space astrometry mission has been performed. Thousands to tens of thousands of transiting planets should be detected with GAIA.

The baseline of GAIA is the study of the formation and evolution ofthe Milky Way from astrometric and photometric measurements. Themission displays a remarkable versatility in its applications,including a significant impact in fundamental physics. In thefollowing I will try to define the relationship between astrometry andfundamental physics, before considering in more detail thedetermination of the space curvature and the study of the nonlinearity of gravity from the astrometric measurements. It is shownthat GAIA is perfectly at home to sense the bending of light-rays inthe solar gravitational field and should be able to determine the PPNparameter γ with a precision between 10-6 and 10-7,much better than any other determination expected by 2015. Afavorable combination of distances and eccentricities on a handful ofminor planets will permit to search for the relativistic perihelionprecession. The parameter β should be ascertained to 10-3-10-4 provided the solar quadrupole moment is not solvedsimultaneously and constrained from other sources. This achievableaccuracy rests also on assumptions regarding the reconstruction oforbits of minor planets from GAIA-only observations.

Due to radiative acceleration and gravitational settling, stars would display vast differences in their surface composition, if these were not smoothed out, at least partly, by some competing processes. Possible mechanisms have been suggested and examined by Georges Michaud and his collaborators: mass loss, turbulent mixing and meridional circulation. They will be discussed here in the light of more recent developments.

Sparse optical interferometric arrays of many apertures can produce direct images in the densified-pupil mode, also called “hypertelescope” mode. Pending the introduction of adaptive optics for cophasing, indirect images can also be reconstructed with speckle imaging techniques. But adaptive phasing is preferable, when a sufficiently bright guide star is available. Several wave sensing techniques, by-products of those used on monolithic telescopes for some of them, are potentially usable. For cophased direct images of very faint sources in the absence of a natural guide star, a modified form of the Laser Guide Star techniques demonstrated on conventional and segmented telescopes is described. Preliminary testing in laboratory suggests further investigation. Recorded images, assumed co-phased, are also improvable post-detection with optical aperture-synthesis techniques such as Earth rotation synthesis, where data from successive exposures are combined incoherently. Nevertheless, the gain becomes modest if hundreds of sub-apertures are used. Image deconvolution techniques are also applicable, if suitably modified as demonstrated by Aime et al. (2012), and Mary (2012). Their modified deconvolution algorithms can extend the Direct Imaging Field (also called Clean Field) of hypertelescopes. More sub-apertures at given collecting area, implying that their size is reduced, improve the direct-imaging performance. The predictable trend thus favors systems combining hundreds of sub-apertures of modest size, if workable designs can be evolved. One such design, the “Ubaye Hypertelescope” entering the initial testing phase in the southern Alps, has a fixed spherical meta-mirror with a 57 m effective aperture, expandable to 200 m. Preliminary results suggest that larger versions, whether spherical or active paraboloidal, can reach a kilometric aperture size at terrestrial sites having a suitable concave topography. In space, hypertelescope meta-apertures spanning up to 100 000 km are in principle feasible in the form of a flotilla of mirrors, driven by micro-thrusters or by the radiation pressure of the Sun or lasers.

On behalf of ESA and the Planck Scientific Collaboration, we present anoverview of the European Space Agency's Planck mission, itsscientific objectives and the main elements of its technical design.The current programmatic status of Planck within ESA's Scientific Programme,implementation plans, and near-term milestones arealso outlined.

Among the A/B stars, about 5% host large-scale organised magnetic fields. These magnetic stars show also abundance anomalies in their spectra, and are therefore called the magnetic Ap/Bp stars. Most of these stars are also slow rotators compared to the normal A and B stars.Today, one of the greatest challenges concerning the Ap/Bp stars is to understand the origin of their slow rotation and their magnetic fields. The favoured hypothesis for the latter is that the fields are fosils, which implies that the magnetic fields subsist throughout the different evolutionary phases, and in particular during the pre-main sequence phase. The existence of magnetic fields at the pre-main sequence phase is also required to explain the slow rotation of Ap/Bp stars. 
During the last 3 years we performed a spectropolarimetric survey of the Herbig Ae/Be stars in the field and in young clusters, in order to investigate their magnetism and rotation. These investigations have resulted in the detection and/or confirmation of magnetic fields in 8 Herbig Ae/Be stars, ranging in mass from 2 to nearly 15 solar masses. In this paper I will present the results of our survey, as well as their implications for the origin and evolution of the magnetic fields and rotation of the A and B stars.

Massive stars feature highly energetic stellar winds that interact whenever two such stars are bound in a binary system. The signatures of these interactions are nowadays found over a wide range of wavelengths, including the radio domain, the optical band, as well as X-rays and even γ-rays. A proper understanding of these effects is thus important to derive the fundamental parameters of the components of massive binaries from spectroscopic and photometric observations.

Main theoretical formulae and some computational results ofevolutionary segregation of Hg isotopes due to light-induced driftin the atmospheres of chemically peculiar stars have beenrepresented.

The Wide-field High-resolution Infrared TElescope (WHITE) that we propose for Dome Cwill be dedicated in the first years of its life to carry out a few legacy surveys (well-focused in terms of science objectives and time).
WHITE would have an angular resolution of ~0.3'' uniform over ~0.7 sq. deg. in the wavelength range 1 µm to 5 µm, which means that we will very efficiently use all the available observational time during night time and day time. Moreover, the deepest observations will be performed by summing up shorter individual frames. We will obtain temporal information that can be used to study variable objects.
The three key science objectives of WHITE are: 1) A survey of the Magellanic Clouds to make a complete census of young stellar objects in the Clouds and in the Bridge and to study their star formation history and the link with the Milky Way. The interaction of the two Clouds with our Galaxy might be the closest example of a minor merging event that could be the main driver of galaxy evolution in the last 5 Gyrs. 2) Establishing of the first sample of dusty supernovae at z < 1.2 in the near infrared range (1.0 - 5.0 µm) to constrain the equation of state of these obscured objects, study the formation of dust in galaxies, and build the first high resolution sample of high-redshift galaxies observed in their optical frame 3) A very wide weak lensing survey that would allow to estimate the equation of state of dark energy in a way that would favourably compete with space projects.

We investigate the multiplicity as a function of stellar mass. For this purpose we have created three complete samples of O, B, and FGK stars and performed multi-epoch, high-resolution (R ∼ 50 000) optical spectroscopy. The current results for the O-type stars suggest a multiplicity fraction of more than 80%. Many O-type systems contain components of similar mass. The multiplicity fraction for B stars seems to decrease from 70% to 20%. We argue that this general decrease is most likely due to observational biases; however, similar-mass systems – like common for O-type stars – seem to vanish toward later B-types. Within the sample of F stars we observe an increasing multiplicity fraction with primary mass (∼50% – 80%); simultaneously there is a decrease of single stars toward the A-type regime. Closer inspection of spectroscopic binaries – either by spectral disentangling or by common proper motion studies – reveals higher-level systems in each mass range.

A short overview is presented of several topics concerning the evolution of the Milky Way (MW) in a cosmological context. In particular, the metallicity distribution of the MW halo is derived analytically and the halo metallicity and abundance patterns are compared to those of Local Group galaxies. The inside-out formation of the MW disk is supported by the observed evolution of the abundance gradients, while their magnitude suggests that the role of the Galactic bar has been negligible. Finally, the empirical foundations (age-metallicity relation and metallicity distribution) of the evolution of the solar neighbourhood, which is the best studied galactic sub-system, have been seriously questioned recently.

In the last two decades, considerable efforts have been devoted to the study of white dwarfs pulsators. Owing to ground-based multi-sites observational campaigns, and more recently to the long time-based high-precision photometric observations with the Kepler satellite, a large number of pulsating white dwarfs have been studied through the asteroseismology method. I emphasize here the accuracy that this method achieves on the determination of the total mass, one of the fundamental stellar parameter that can be derived from asteroseismology, among others. Then I discuss the issue of the age determination, emphasizing the contribution of the neutrinos cooling and the importance of the outer layer mass fraction. I show that some observations throw some doubts on the assumption that the cooling is the only cause of the observed frequency variations. Finally I summarize the results demonstrating that the entire stellar angular momentum is lost during the evolutionary phases prior to the white dwarf stage. While the asteroseismology of white dwarf stars has given a rich harvest of results on their internal structure and evolution, there are still some challenges to face. Determining accurate mass of the outer layers, specifically for the DA white dwarfs, is one of them. An increasing number of white dwarf pulsators are now known to exhibit frequency and amplitude temporal variations. The physical mechanism producing such variabilities has to be identified.

We have investigated the dissociative recombination (DR) of theC6D6+and C6D7+ions using the CRYRING heavy-ion storage ring at Stockholm University,Sweden. Thedissociative recombination branching ratios were determined at minimal collision energy, showing that the DR of both ions was dominated by pathways keeping the carbon atomstogether in one product. The absolute reaction cross sections for the titular ions arebest fitted by σ(Ecm [eV]) = 1.3 ± 0.4 × 10-15(Ecm [eV])−1.19 ± 0.02 cm2(C6D6+)and σ(Ecm [eV]) = 1.1 ± 0.3 × 10-15(Ecm [eV])−1.33 ± 0.02 cm2(C6D7+)in the intervals 3-300 meV and 3-200 meV respectively. The thermal rate constants of thetitular reactions are best described by:k(T) = 1.3 ± 0.4 × 10-6(T/300)−0.69 ± 0.02cm3s-1 for C6D6+and k(T) = 2.0 ± 0.6 × 10-6 (T/300)−0.83 ± 0.02cm3s-1 for C6D7+.These expressions correlates well with earlier flowing afterglow studies on the sameprocess.

We investigated particle acceleration and shock structure associated with an unmagnetizedrelativistic jet propagating into an unmagnetized plasma. Strong magnetic fields generatedin the trailing shock contribute to the electrons transverse deflection and acceleration.We have calculated, self-consistently, the radiation from electrons accelerated in theseturbulent magnetic fields. We found that the synthetic spectra depend on the bulk Lorentzfactor of the jet, its temperature and strength of the generated magnetic fields. We havealso investigated accelerated electrons in strong magnetic fields generated by kineticshear (Kelvin-Helmholtz) instabilities. The calculated properties of the emergingradiation will guide our understanding of the complex time evolution and/or spectralstructure in gamma-ray bursts, relativistic jets in general, and supernova remnants.

This contribution lays out the scientific foundations of the project ExoMol. This project will produce molecular line lists for all molecules considered to be important for the modelling atmospheres of exoplanets and cool stars, which are prerequisites for the spectroscopic characterization of the atmospheres of these astrophysical objects. Towards this end 25 species are identified as key ones for meeting current demands for atmospheric models of exoplanets and brown dwarfs, impeded by the lack of fundamental data on the absorption of these species. The production of comprehensive and very large rotation-vibration and rotation-vibration-electronic line lists requires a mixture of first principles quantum mechanical methods and empirical tuning based on laboratory spectroscopic data. ExoMol will rely on these methodologies and make extensive use of state-of-the-art computing.

We present a new multi–fluid, grid MHD code PIERNIK, which is based on the Relaxing TVD scheme (Jin & Xin 1995). The original scheme (see Trac & Pen 2003; Pen et al 2003) has been extended by an addition of dynamically independent, but interacting fluids: dust and a diffusive cosmic ray gas, described within the fluid approximation, with an option to add other fluids in an easy way. The code has been equipped with shearing–box boundary conditions, and a selfgravity module, Ohmic resistivity module, as well as other facilities which are useful in astrophysical fluid–dynamical simulations. The code is parallelized by means of the MPI library. In this paper we present Ohmic resistivity extension of the original Relaxing TVD MHD scheme, and show examples of magnetic reconnection in cases of uniform and current–dependent resistivity prescriptions.

3-D simulations suggest that the atmospheres of red supergiants are subject to large-amplitude convective motions, which are suspected to generate supersonic motions and shocks. We perform tomography of supergiant-star atmospheres, on temporal series of high-resolution spectra and on 3-D hydrodynamical synthetic spectra. The tomographic technique is improved by the computation of the contribution function, which is used to construct numerical spectral masks probing different optical depths. This exploratory work allows us to put spatial and temporal constraints on velocity fields predicted by 3-D model atmospheres.

The Photodetector Array Camera and Spectrometer on Herschel provides imaging line spectroscopy and imaging photometry in the 55–210 μm wavelength band. In photometry mode, two filled silicon bolometer arrays with 16×32 and 32×64 pixels, respectively, are used to simultaneously image two bands, 60–85 μm or 85–130 μm and 130–210 μm, over a field of view of ~1.75'×3.5', with Nyquist beam sampling in each band. In spectroscopy mode, two Ge:Ga photoconductor arrays (stressed and unstressed) with 16×25 pixels, each, are used to image a field of ~50''×50'', resolved into 5×5 pixels, with a spectral resolution of ~175 km s-1 and an instantaneous spectral coverage of ~1500 km s-1. In both modes the performance is expected to be not far from background-noise limited, with sensitivities (5σ in 1 h) of ~4 mJy or 3–20×10-18 W/m2, respectively. We summarise the design of the instrument and its subunits, describe the observing modes in combination with the telescope pointing modes, report results from instrument level performance tests of the Flight Model, and present our current prediction of the in-orbit performance of the instrument.