Optical studies of ultraluminous X-ray sources (ULX) in nearby galaxies have turned out to be instrumental in discriminating between various models including the much advertised intermediate mass black hole hypothesis and various beaming scenarios. Here we report on ESO VLT and SUBARU observations of ULX that have revealed the parent stellar clusters with ages of some 60 million years in two cases. Thus we are able to derive upper limits of about 8 M$_{\odot}$ for the mass donors in these systems. The optical counterparts are dominated by X-ray heated accretion disks, and the discovery of the He II $\gamma$4686 emission line now allows to derive dynamical masses in these systems. Apparent radial velocity variations of 300 km/s have been detected in NGC 1313 X-2 which, if confirmed by further observations, would exclude the presence of IMBH in these systems.

The early results on astrochemistry from the Cores to Disks (c2d) Legacy program are summarized. The c2d program focuses on the formation of low-mass stars in nearby (within about 300 pc) clouds. Spectroscopy with IRS includes the following topics: ices seen against background stars, in protostellar envelopes, and in disks; grain growth and mineralogy, PAHs, and gas in circumstellar disks.

Our understanding of the physical and chemical structure of pre-stellar cores, the simplest star-forming sites, has significantly improved since the last IAU Symposium on Astrochemistry (South Korea, 1999). Research done over these years has revealed that major molecular species like CO and CS systematically deplete onto dust grains in the interior of pre-stellar cores, while species like N2H+ and NH3 survive in the gas phase and can usually be detected toward the core centers. Such a selective behavior of molecular species gives rise to a differentiated (onion-like) chemical composition, and manifests itself in molecular maps as a dichotomy between centrally peaked and ring-shaped distributions. From the point of view of star-formation studies, the identification of molecular inhomogeneities in cores helps to resolve past discrepancies between observations made using different tracers, and brings the possibility of self-consistent modelling of the core internal structure. Here I present recent work on determining the physical and chemical structure of two pre-stellar cores, L1498 and L1517B, using observations in a large number of molecules and Monte Carlo radiative transfer analysis. These two cores are typical examples of the pre-stellar core population, and their chemical composition is characterized by the presence of large ‘freeze out holes’ in most molecular species. In contrast with these chemically processed objects, a new population of chemically young cores has begun to emerge. The characteristics of its most extreme representative, L1521E, are briefly reviewed.

REM is a fast slewing automatic telescope dedicated to the prompt observation of GRB afterglows. The telescope automatically reacts to GCN alerts, beginning follow-up observations in both infra-red and optical wavelengths. Recent observations of GRBs have shown the capabilities of REM to begin follow up observation in the order of 10s of seconds after the burst.

The Spitzer Space Telescope (SST), aloft for over two years at time of writing, has so far devoted almost 600 hours of observing time to Solar System science, and small bodies make up a significant fraction of the objects that have been observed. For the first time we now have high accuracy mid-infrared data to study the fundamental mineralogical and physical properties of a large number of objects of different types. In this paper we review some of the exciting recent results derived from SST photometry (in six bands from 3.6 to 70 $\mu$m) and spectroscopy (from 5 to 40 $\mu$m) of asteroids and comets. The observations reveal their spectral energy distributions (SEDs), and we discuss three important science goals that can be addressed with these data: (1) finding compositional diagnostics of these objects, (2) determining their bulk thermal properties, and (3) understanding the surface evolution of primitive and icy bodies. We focus primarily on comet-asteroid transition objects, low-albedo asteroids, cometary nuclei, Trojans, Centaurs, and trans-Neptunian objects. In particular, we will show: emissivity features in the SEDs and identification of the compositional sources, the constraints on thermal inertia and infrared beaming through the samples of the thermal continuum, and an intercomparison of albedos across dynamically-related bodies.

As shown in our first poster, in a recent survey of M33 with XMM-Newton we detected the X-ray source population of this nearby spiral galaxy down to the (0.2-4.5) keV luminosity of $10^{35}$ erg s$^{-1}$, a factor of 10 deeper than in previous observations. The majority of the detected sources was classified using, in many cases, only their X-ray properties. In particular, 8 new X-ray binary (XRB) candidates were selected, based on their long-term X-ray light curves. We also classified supernova remnants (SNRs), super-soft sources (SSS), AGN, foreground stars and a population of ‘hard’ sources using the hardness ratio (HR) method. A detailed spectral and timing analysis of the brightest sources is in progress. We present a few examples of spectra for particular source classes. We find that bright ‘hard’ sources can be divided into two broad families: one best modelled by a powerlaw with photon index in the range of 1.0–2.0, and the other displaying disk blackbody spectra with kT of 0.8 to 1.5 keV.

The recent evidence of a peculiar distribution of X-ray sources in the elliptical galaxy NGC 4261 reported by Zezas et al. has prompted us to study this galaxy combining archive X-ray and optical observations, from Chandra, INT, and HST. We find that a sizable fraction of the X-ray sources has a globular cluster as optical counterpart. This together with the shape of the luminosity function of the X-ray sources suggest that they are accreting low-mass binaries. We further show a remarkable similarity in the anisotropy of the projected spatial distributions of the optical and X-ray sources, which leads us to conclude that the spatial anisotropy of the X-ray sources in NGC 4261 is due to the anisotropy of the globular cluster population.

Comets are among the most primitive bodies of the solar system, and their chemical composition is rich in information on the protosolar nebula and its possible connection with interstellar cloud chemistry. Comets are also a source of light atoms and, possibly, prebiotic organic molecules for the early Earth. We know better and better the abundances of cometary volatiles through spectroscopy, mainly at infrared and radio wavelengths. Another crucial component of cometary matter – organic refractories – is still poorly characterized, however.

We summarize here the $\sim$30 abundances and $\sim$20 upper limits obtained on cometary volatiles and highlight a few species and problems: ethylene glycol, NS, HNC/HCN, $^{14}$N/$^{15}$N, the origin of CN, CS$_{2}$, PAHs, and H$_{2}$O. Comet-to-comet variations and comet internal heliocentric variations can now be studied, and cometary comas can be mapped with a variety of techniques. We list a number of temperature indicators, for they can help understand the relation between IS and cometary matters, which present both a global similarity but also marked differences, such as the high ethylene glycol content of comets.

We conclude by outlining a few key problems to be addressed by future ground-based and space instruments or by cometary sample analysis. For many species, we stress that laboratory data are missing on spectroscopy, photodissociation and collisions with H$_{2}$O.

Properties of small, heliocentric bodies in the solar system share many attributes because of their small sizes, yet vary in other ways because of their different locations of formation and the diverse subsequent evolutionary processes that have affected them. Our insights concerning their properties range from highly detailed knowledge of a few specific bodies (like Eros), to rich knowledge about unspecific bodies (meteorite parent bodies), to no knowledge at all (other than existence and rough limits on size) concerning much smaller and/or more distant bodies. Today's state of learning about physical properties of TNOs is analogous to that for main-belt asteroids 35 years ago. This invited review attempts to elucidate linkages and differences concerning these populations from the highly heterogeneous data sets, emphasizing basic properties (size, shape, spin, density, metal/rock/ice, major mineralogy, presence of satellites) rather than the highly detailed knowledge we have of a few bodies or their dynamical properties. The conclusion is that there are vital interrelationships among these bodies that reinforce the precept that guided the original ACM meetings, namely that we should all think about small bodies in an integrated way, not just about subsets of them, whether divided by size, composition, or location.

The formation of H2 and HD molecules on interstellar dust grains is studied using rate equation and master equation models. Rate equations are used in the analysis of laboratory experiments, which examine the formation of molecular hydrogen on astrophysically relevant surfaces. However, under interstellar conditions, rate equations are not suitable for the calculation of reaction rates on dust-grain surfaces. Due to the low flux and the sub-micron size of the grains, the populations of H and D atoms on a single grain are likely to be small. In this case the reaction rates are dominated by fluctuations and should be calculated using stochastic methods. The rate of molecular hydrogen formation in interstellar clouds is evaluated using the master equation, taking into account the distribution of grain sizes.

The low-frequency (LF) timing noise contaminates residuals of time-of-arrivals (TOAs) of pulsar signals on long time intervals and in some cases can be explained by external astronomical factors not intrinsically related to the pulsar itself. A number of millisecond pulsars located in globular clusters show the LF noise presence in their rotational phase. We discuss a possible origin of this noise as caused by random time variations in the Shapiro time delay caused by flybys of stars of the globular cluster passing near the pulsar line of sight. The Shapiro time delay is integrated over space of parameters characterizing statistical ensemble of stars in the globular cluster and its long-term indeterministic time variation is obtained. We use this result for numerical simulations of the autocovariance function of the LF timing noise and show it can be used for the measuring of the density profile distribution in the globular cluster.

Shell-like supernova remnants (SNRs) are primary candidates for the origin of Galactic cosmic rays. However, among the known SNRs (about 220), only a small fraction has been known to exhibit the synchrotron X-ray spectrum, that is considered to be a piece of evidence for high energy particle acceleration. Synchrotron X-ray emitting SNRs are known to be systematically radio-quiet compared to the SNRs that do not emit synchrotron X-rays. Therefore, most synchrotron X-ray emitting SNR candidates may have escaped detection in the previous systematic radio surveys. On the other hand, hard X-ray surveys are effective to search for synchrotron X-ray emitting SNRs, because of its penetration power. Thus we have searched for SNRs in the ASCA Galactic Plane Survey data, the first Galactic imaging survey in $>$2 keV, and discovered 14 candidates. Deep follow-up observations with ASCA, XMM, or Chandra on 5 of them revealed 2 sources to be synchrotron X-ray emitting SNRs. Furthermore we confirmed non-thermal X-ray spectra from the other 3 sources, though the origin is yet unknown. We report the observational results and discuss the X-ray origin.

Rich molecular complexity has been shown to exist in star forming regions primarily through millimeter to submillimeter single-dish spectral line surveys or searches over the years. With a few case studies, we demonstrate that interferometric observations are a powerful tool for advancing our knowledge of the chemical processes related to the formation of complex organic molecules in these regions. In particular, interferometers are sensitive to compact structures, such as those of the so called “hot molecular core” sources where complex organics are almost exclusively found. The high angular resolutions achieved by interferometers allow us to better spatially discriminate chemical differentiation and, possibly, evolutionary effects.

The detection of interstellar molecules relies on the precise knowledge of spectral line positions from laboratory measurements. Technical developments of recent years have led to an extension of the accessible spectral range towards shorter wavelengths. New telescopes like SOFIA, the HIFI instrument aboard the Herschel satellite, and ALMA will be used for astrophysical observations in the terahertz region. The Cologne group has developed precise spectrometers to study molecules of astrophysical importance under laboratory conditions and to obtain characteristic spectra for their possible detection in space. We present recent results on light hydrides, carbon-chain molecules and more complex species.

We report the discovery of broad mid-infrared resonances in the outer regions of the Red Rectangle outflow (Markwick-Kemper et al. 2005). The peak position and the strength of the resonances vary spatially, but the full width at half maximum, as well as the shape of the feature, appears remarkably constant. While emission due to polycyclic aromatic hydrocarbons (PAHs) is also present at these locations, we show that PAHs cannot be the carriers of these new components. Instead, we argue that these resonances are caused by solid state components, perhaps simple Mg-Fe-oxides. The presence of such O-rich species in the otherwise C-rich outflows further complicates the picture of the formation and chemistry of the Red Rectangle nebula.

The population of small bodies of the outer Solar System is composed by objects of different kind and size, such as comets, Kuiper Belt objects and Centaurs, all sharing however a common characteristic, that is to be rich in ices and other volatiles. The knowledge of the composition and properties of these bodies would help in better understanding the processes that shaped the solar nebula at large heliocentric distances and determined the formation and evolution of the planets. A large number of observational results are now available on these bodies, due to successful space missions and increasingly powerful telescopes, but all our instruments are unable to probe the interiors. However, we are beginning to see how these seemingly different populations are related to each other by dynamical and genetic relationships. In this paper we try to see what could be their thermal evolution and how and when it brings to their internal differentiation. In fact, in this way we can try to foresee what should be the surface expression of their differentiation and evolution and try to link the surface properties, as probed by instruments, with the interior properties. One thing to note about the cometary activity is that it is well interpreted when assuming that the comets are small, fragile, volatile-rich and low-density objects. This view, despite of the strong differences noted in the few comet nuclei observed in situ, has not been disproved. On the other side, the observations of the Kuiper belt objects are possibly indicating that they are large, probably collisionally evolved objects (Farinella & Davis 1996), maybe with larger densities. We are now facing a kind of paradox: we have from one side the comets, and from the other side a population of much denser and larger objects; we know that a dynamical link exists between them, but how can we go from one type of population to another? In this paper the current status of our knowledge on the subject is reviewed, taking into account the results of thermal modeling and the results of observations.

Chandra observations of early-type galaxies have resolved large populations of low-mass X-ray binaries (LMXBs) in early-type galaxies. The majority of these observations have been snapshots on the order of a day or less. In our own Galaxy, LMXBs are known to exhibit a range of luminosity and spectral variability. Multi-epoch observations of early-type galaxies are just beginning to explore the regime of variability on timescales of days to years. We present results for NGC 4365 and NGC 4697, and compare them to the Milky Way.

Before the discovery of the first member of the Kuiper belt in 1992, the trans-Neptunian population was supposed to lie on a flat disk and each member would follow a barely eccentric orbit. While less conventional orbits for the trans-Neptunian objects were being discovered, our understanding of its orbital structure and origin was continually changed. A basic classification of the trans-Neptunian population as to their orbits identifies a classical low inclination Kuiper belt population, a resonant population, a high inclination Kuiper belt population, a scattered population and an extended population. Several mechanisms have been proposed to explain the orbital architecture of the Kuiper belt population. Presently, the most plausible scenarios are unequivocally related with the primordial planetary migration induced by a planetesimal disk. Low inclination orbits in the Kuiper belt may have been moderately pushed out from a dynamically cold primordial disk by the resonance sweeping mechanism. The origin of high inclination objects in the classical Kuiper belt is however to be found in a primordial Neptune scattered population, through a perihelion increasing mechanism based on secular resonances. Another push-out mechanism based on the sweeping of the 1:2 resonance with Neptune has also been invoked to explain the low inclination orbits in the classical Kuiper belt. Assuming these last two mechanisms, Kuiper belt objects do not need to have been formed in situ. This kind of formation process would demand a quite large original mass in the Kuiper belt region, which would have brought Neptune beyond its present position at 30 AU. Thus with the exception of the low inclination classical Kuiper belt objects and a few resonant ones, all other trans-Neptunian objects are present or past scattered objects. This notion also includes the case for Sedna, so far the only certain member of the extended population. In its most plausible formation scenario, it was a primordial scattered object by Neptune whose perihelion was increased by the close passage of a star.

We present optical observations of an ultraluminous X-ray source (ULX) in Holmberg IX, a dwarf galaxy near M81. The ULX has an average X-ray luminosity of some $10^{40}$ erg/s. It is located in a huge (400pc$\,{\times}\,$300pc) ionized nebula being much larger than normal supernova remnants. From the observed emission lines (widths and ratios) we find that the structure is due to collisional excitation by shocks, rather than by photoionization.

We identify the optical counterpart to be a 22.8 mag blue star ($M_V=-5.0$) belonging to a small stellar cluster. From isochrone fitting of our multi-colour photometry we determine a cluster age of some 60 Myr. We also discovered strong stellar HeII$\lambda$4686 emission (equivalent width of $\mbox{10 \AA}$) which proves the identification with the X-ray source, and which suggests the presence of an X-ray heated accretion disc around the putative black hole.

With the detection of relativistic broad emission lines in MCG 6-30-15 (Tanaka 1995) X-ray observations have become an important tool to test the direct environment of black holes.

XMM-Newton observations were the basis of remarkable progress in different directions in recent years. On the one side the birth and the growth of black holes could be addressed in detail. On the other side several observations allowed the study of the strong gravitational field in the vicinity of black holes.

The talk provides an overview of XMM-Newton observations of black holes: starting from the creation of stellar-mass black holes, through mass growth via accretion disks and occasional tidal disruption events, up to intermediate and supermassive black holes in the centre of active and non-active galaxies. Special attention will be given to the achieved status in the determination of the measurable quantities of black holes, i.e. mass and spin.