We show that the XCO factor, which converts the CO luminosityinto the column density of molecular hydrogen has similar values for dense, fullymolecular gas and for diffuse, partially molecular gas. We discuss the reasons of thiscoincidence and the consequences for the understanding of the interstellar medium.

This report provides the recommendations of ARENA Working Group 1 concerning the development of and objectives for a wide-field, optical/infrared, 2.5 m class telescope for Antarctica. It discusses the key science drivers for such a telescope, the performance and capabilities it should have, and the logistics and infrastructure issues relevant to its construction and operation.

The extreme cleaning of stellar images, needed for distinguishing their planets and especially those analogous to the Earth, requires coronagraphy and apodization. These techniques suppress the diffraction rings, but not the residual speckles resulting from the bumpiness of the optical surfaces.Several methods, coherent and incoherent, can in principle remove these speckles, but some of them are affected if the star is slightly resolved. With the future large hypertelescopes, spanning 100 kilometers or more to resolve the details of exo-Earths, this could require cleaning procedures applied separately for each sub-aperture before recombining the beams.

The existence of coronal plasmoids has been postulated for many years in order to supply material to streamers and possibly to the solar wind (SW). The W-L SoHO C2 Lasco coronagraph observations were made under the 2.2 solar radii (R0) occulting disk to look at the ultimate sources of the SW; EUV imagers are preferably devoted to the analysis of the corona on and very near the solar disk. Here, in addition to eclipse white-light (W-L) snapshots, we used the new SWAP space-borne imager designed for the systematic survey of coronal activity in the EUV lines near 17.4 nm, over a field of view (FOV) up to 2 R0. Using summed and co-aligned images, the corona can then be evaluated for the 1st time up to the limit of this FOV. At the time of the July 11, 2010, solar total eclipse a 20h continuous run of observations was collected, including images taken during eclipse totality from several ground observing locations where W-L data were collected. A plasmoid-like off-limb event was followed using the SWAP summed

We present color-magnitude diagrams (CMD) reaching the oldest main sequence turn offs for three fields in the Fornax dwarf spheroidal galaxy, obtained with FORS1 at the VLT. One of them is situated at the center of the galaxy while the other two are located at a distance of 10′ form the center. We determine the full star formation history (SFH) of the central field, extending to the first star formation events.

Although the theoretical study of very low metallicity (Z) and metal–free stars is not new,their importance has recently greatly increased since two related fields have been developing rapidly. The first iscosmological simulations of the formation of the first stars and of the reionisation period. The second is the observations of extremely metal poor stars. In this paper, we present pre–supernova evolution models of massive rotating stars at very low Z (Z = 10-8) and at Z = 0. Rotation has astrong impact on mass loss and nucleosynthesis. Models reaching break–upvelocities lose up to ten percents of their initial mass.In very low Z models, rotational and convective mixing enhancessignificantly the surface content in carbon, nitrogen and oxygen (CNO)when the star becomes a red supergiant. This induces a strong massloss for stars more massive than about 60 M๏. Our models predict typeIb,c supernovae and gamma–ray bursts at very low Z. Rotational mixingalso induces a large production of CNO elements, in particular ofprimary nitrogen. The stellar wind chemical composition is compatible with themost metal–poor star know to date, HE 1327–2326, for CNO elements. Ourmodels reproduce the early evolution of nitrogen in the Milky Way.

In order to increase in Spain the social interest in the study of interplanetary matter (asteroids, comets and meteoroids) we created the Spanish Photographic Meteor Network (SPMN) in 1997. This network has been dedicated to studying interplanetary matter with participation of researchers from three universities (Universitat Jaume I, Universitat de Barcelona and Universitat de València), the Institut d'Estudis Espacials de Catalunya (IEEC) and the Instituto de Astrofísica de Andalucía and it is also supported by the Atmospheric Sounding Station at El Arenosillo (INTA-CEDEA) and by theExperimental Station La Mayora (EELM-CSIC). In order to promote the participation of amateurs, our homepage (www.spmn.uji.es) presents public information about our research explains how amateur astronomers can participate in our network. In this paper we give some examples of the social role of a Fireball Network in order to give a coherent explanation to bright fireball events. Moreover, we also discuss the role of this kind of research project as a promoter of amateur participation and contribution to science. In fact, meteor astronomy can become an excellent area to form young researchers because systematic observation of meteors using photographic, video and CCD techniques has become one of the rare fields in astronomy in which amateurs can work together with professionals to make important contributions. We present here some results of the campaigns realized from the formation of the network. Finally, in a new step of development of our network, the all-sky CCD automatic cameras will be continuously detecting meteors and fireballs from four stations located in the Andalusia and Valencian communities by the end of 2005. Additionally, during important meteor showers we plan to develop fireball spectroscopy using medium field lenses.

Modelling the UV/optical - infrared/submm SEDs of spiral galaxies observed with Herschel will be an essential tool to quantitatively interpret these observations in terms of the present and past star-formation activity of these systems. In this lecture we describe the SED modelling technique we have developed, its applications and tests of its predictions. We show that both the panchromatic SED modelling of individual galaxies and the B-band attenuation-inclination relation of large statistical samples suggest that spiral galaxies in the nearby Universe behave as optically thick systems in their global properties and large-scale distribution of light (central face-on B-band opacity of τBf~4). However disk galaxies are very inhomogeneous systems, having both optically thick components (e.g. spiral arms), and optically thin components (e.g. the interarm regions), the latter making galaxies transparent to background galaxies.

The paper focuses on collisional excitation rates of molecules by He, H2 andelectrons relevant to the interstellar medium, it discusses currently available data,presents very recent work and outlines new work being carried out in order to provide easyaccess to these molecular data. In particular outlines of the latest developments in theBASECOL database and of the “Virtual Molecular Data Centre” capabilities are provided.

One of the most fundamental discoveries in physics and astrophysicswas made with the discovery of pulsars. Ever since, pulsars – andlater in particular binary and millisecond pulsars – have beenstudied as extreme end-states of stellar evolution, as super-denseobjects, as radio and high-energy sources, as probes for theinterstellar medium, and as super-precise clocks for fundamentalexperiments in gravitational physics. This article reviews some of theexciting applications of pulsar physics and the amazing prospects thatare promised by the advent of the Square-Kilometre-Array (SKA).

We briefly review the feedback effects of massive stars, via their stellar winds and supernova explosions, on the star-forming regions in which they were born. We give a few examples, spanning a wide range of spatial scales, from ∼100 pc out to ∼10 kpc: the so-called “Local Bubble” (in reality an open bipolar structure extending on both sides of the galactic disk); the Extended Orion Nebula and its open cavity filled with a hot, MK outflowing plasma; the Great Carina Nebula and its extended diffuse X-ray emission; the 30 Dor region in the LMC and its various bubbles; and the extended, bipolar outflow of the prototype starburst galaxy M 82, influenced by a nearby group of galaxies. We conclude by stressing the similarity of these phenomena across all spatial scales, galactic and extragalactic.

Here we briefly summarize our long period experience of constructing and operatingwide-field monitoring cameras with sub-second temporal resolution to look for opticalcomponents of GRBs, fast-moving satellites and meteors. General requirements for hardwarefor such systems are discussed along with algorithms of real-time detection andclassification of various kinds of short optical transients. We also give a status reporton the next generation, multi-objective and transforming monitoring system, theMegaTORTORA, whose 6-channel (Mini-MegaTORTORA-Spain) and 9-channelprototypes (Mini-MegaTORTORA-Kazan) we are building now at SAO RAS. This system combines awide field of view with subsecond temporal resolution in monitoring regime, and is able toreconfigure itself, in a fractions of second, to follow-up mode which has bettersensitivity and provides us with multi-color and polarimetric information on detectedtransients simultaneously.

Severe interstellar extinction toward the Galactic plane has prevented the investigation of stellar populations in that region. Pulsating variable stars, particularly Cepheids and Miras, are useful tracers because their distances and ages can be determined accurately. Infrared observations of these variable stars in the obscured regions can provide useful information about the hidden parts of the Galaxy. These objects can also provide complimentary information to observations made by the Gaia spacecraft because highly-obscured objects cannot be detected by Gaia. We have carried out a near-infrared survey of variable stars near the Galactic bulge, between − 10 and + 10 degrees in galactic longitude, using the IRSF 1.4 m telescope and SIRIUS near-infrared camera in South Africa. Here as an initial result we report the discovery of 19 classical Cepheids behind the bulge.

It can be argued that all astrophysical jets, from lowly sub-stellar objects such as young brown dwarfs to massive black holes at the centre of AGN, are generated by the same basic physical mechanism. While the nature of that mechanism is still debated, jets from young stars may represent our best chance of deciphering it. There are several reasons for this statement. First of all they are nearby, thus affording us not only high spatial resolution studies of the “central engine” but also time-resolved analysis of their kinematics. Moreover as they radiate emission lines, spectroscopy can reveal radial velocities, temperature, density, ion fraction, etc., along their flow. This wealth of data is a challenge to the theorist/computational simulator but also a highly effective means of discriminating between models. In addition, the observations tightly constrain laboratory experiments. Here, I briefly review what is known about conditions in jets from young stars as a guide to experiments, their generation including their link with accretion disks, and their evolution from the earliest proto-stellar to pre-main sequence phase.

The difference in density profiles of the contributions from different density peaks to dark matter halos results in certain expectations about the Milky Way's stellar halo. We cut our simulated halo stars into two populations: those forming before/during the last major merger, and those accreted after the last major merger. The former population are more centrally located at z = 0, while stars forming in low mass late forming proto-galaxies are spread through the halo. A difference in observed binding energy distinguishes these two populations. We look at possible chemical abundance signatures of the two populations. We also show that galaxies forming in isolated low σ peaks will form from primordial material. Thus, even though the oldest stars are centrally concentrated as they originated in the early collapsing, densest regions, primordial stars would be found distributed throughout the halo. Thus, the lack of observed metal free stars can be taken as directly constraining the Population III IMF, and the lowest metallicity observed stars can be interpreted as holding clues to the chemical yields of Pop III stars.


The spectra of a number of reportedly sharp-line B, A and F stars havebeen observed in a 60-Å window with a resolving power of 120 000.As a first step in analysis of these data, the spectra have beensynthesized to see how well simple models fit. The informationobtained from both successful modelling and from discrepant fits isdiscussed.

Astrometry satellites have common technological issues. (A) Astrometry satellites arerequired to measure the positions of stars with high accuracy from the huge amount of dataduring the observational period. (B) The high stabilization of the thermal environment inthe telescope is required. (C) The attitude-pointing stability of these satellites withsub-pixel accuracy is also required.

Measurement of the positions of stars from a huge amount of data is the essence ofastrometry. It is needed to exclude the systematic errors adequately for each image ofstars in order to obtain the accurate positions. We have carried out a centroidingexperiment for determining the positions of stars from about 10 000 image data.

The following two points are important issues for the mission system of JASMINE in orderto achieve our aim. For the small-JASMINE, we require the thermal stabilization of thetelescope in order to obtain high astrometric accuracy of about 10 micro-arcsec. In orderto accomplish a measurement of positions of stars with high accuracy, we must make a modelof the distortion of the image on the focal plane with the accuracy of less than 0.1 nm.We have investigated numerically that the above requirement is achieved if the thermalvariation is within about 1 K / 0.75 h. We also require the accuracy of theattitude-pointing stability of about 200 mas / 7 s. The utilization of the Tip-tilt mirrorwill make it possible to achieve such a stable pointing.

The VLT-FLAMES Tarantula Survey (VFTS) has acquired multi-epoch spectroscopy of over 800 O, B and Wolf-Rayet stars in the 30 Doradus region with the aim to investigate a number of important questions related to the evolution of massive stars and of cluster dynamics. In this paper, I first provide an overview of the scientific results obtained by the VFTS consortium so far. I then review the constraints obtained on the multiplicity properties of massive stars in 30 Dor and compare them to our recent results from a Milky Way sample.

The resolution criterion for self-gravity in AMR codes derived by Truelove et al.  (1997) based on the Jeans length is a very robust one and thus quite popular. We believe that for some configurations, such as self-gravitating discs, there are reasons to supplement it in order to properly resolve gravitational instabilities and clump formation processes at reasonable computational costs.

We give a review of cosmic ray propagation models. It is shown that the development of the theory of cosmic ray origin leads inevitably to the conclusion that cosmic ray propagation in the Galaxy is determined by effective particle scattering, which is described by spatial diffusion. The Galactic Disk is surrounded by an extended halo, in which cosmic rays are confined before escaping into intergalactic space. For a long time cosmic ray convective outflow from the Galaxy (galactic wind) was believed to be insignificant. However, investigations of hydrodynamic stability and an analysis of ISM dynamics (including cosmic rays) showed that a galactic wind was emanating near the disk, and accelerating towards the halo, reaching its maximum velocity far away from the disk. Therefore convective cosmic ray transport should be important in galactic halos. Recent analysis of the gamma-ray emissivity in the Galactic disk of EGRET data, which showed that cosmic rays are more or less uniformly distributed in the radial direction of the disk, as well as the interpretation of soft X-ray emission in galactic halos, give convincing evidence of the existence of a galactic wind in star forming galaxies.