The observing program of the Nordic Near-Earth-Object Network (NEON) accrues knowledge about the physical and dynamical properties of near-Earth objects (NEOs) using state-of-the-art inverse methods. Photometric and astrometric observations are being carried out at the Nordic Optical Telescope. Here, the NEON observations from June 2004–September 2006 are reviewed. Statistical orbital inversion is illustrated by the so-called Volume-of-Variation method. Statistical inversion for spins and shapes is carried using a simple triaxial shape model yielding analytical disk-integrated brightnesses for both Lommel-Seeliger and Lambert scattering laws. The novel approach allows spin-shape error analyses with the help of large numbers of sample solutions. Currently, such spin-shape solutions have been derived for 2002 FF12, 2003 MS2, 2003 RX7, and 2004 HW. For (1862) Apollo, an unambiguous spin-shape solution has been obtained using the conventional, convex inversion method and, for (1685) Toro and (1981) Midas, the conventional method has been applied repeatedly to map the regime of possible solutions.

I present the analysis of HI data of two nearby dwarf irregular galaxies: DDO 47 and NGC 3741, whose rotation curves are best fitted by a cored halo, while they are inconsistent with an NFW halo. In DDO 47 non-circular motions are too small to explain the discrepancy with the ΛCDM predictions. NGC 3741 has the most extended rotation curve ever observed, in terms of the optical size.

We describe an observation designed to find Hα emission from galaxies at z≃7–12 made using the InfraRed spectrograph (IRS) on the Spitzer Space Telescope.

Infrared dark clouds (IRDCs) are generally assumed to be a promising hunting ground for tracing very early stages of massive star formation. Observations with Spitzer are a viable tool to probe their interiors that are still dominated by strong dust extinction even at 8 μm. With Spitzer/MIPS, we have observed several IRDCs at 24 and 70 micron. We generally find weak 24 micron sources within the IRDCs. However, at 70 micron these sources remain weak and thus indicate lower luminosities at the current state of evolution. Indications for internal substructures exist, separating regions with compact IR sources from even more dark regions.

Under ideal conditions, Earth-based telescopes can observe near-Earth objects (NEOs) continuously from a few days to months during each apparition. Due to the usually complicated dynamics of the Sun-Earth-NEO triplet, the time interval between consecutive apparitions typically ranges from months to several years. On these time scales, exiguous single-apparition sets (SASs) of observations having short observational time-intervals lead to substantial orbital uncertainties. Linking of SASs over apparitions thus becomes a nontrivial task. For example, of a total of roughly 4,100 NEO observation sets, or orbits, currently known, some 2,300 are SASs, for which the observational time interval is less than 180 days. Either these SASs have not been observed at an apparition following the discovery apparition or the linkage of SASs has failed, an option which should preferably be eliminated. As a continuation to our work on the short-arc linking problem at the discovery moment (Granvik & Muinonen, 2005, Icarus 179, 109), we have investigated the possibility of using a similar method for linking exiguous SASs over apparitions. Assuming that the observational time-interval for SASs of NEOs is typically at least one day (minimum requirement set by the Minor Planet Center), the orbital-element probability-density function is constrained as compared to the typical short-arc case with an observational time interval of only a few tens of minutes. Because of the smaller orbital-element uncertainty, we can use the short-arc method (comparison in ephemeris space) for longer time spans, or even do the comparison directly in the orbital-element space (Cartesian, Keplerian, equinoctial, etc.), thus allowing us to assess the problem of linking SASs of NEOs. Due to possible close approaches with the Earth and other planets, and substantial propagation intervals, we have developed new n-body techniques for the orbit computation.

For conclusions, the traditional approach in IAU meetings is to have a highlights speech, in which the most important points of the meeting are stressed. After consulting with the co-chairs of the Scientific Organizing Committee, I decided I would rather discuss the spirit of this meeting from a more conceptual point of view.

The United Nations Office for Outer Space Affairs and the International Heliophysical Year (IHY) community have joined hands to deploy arrays of small, inexpensive instruments such as magnetometers, radio telescopes, GPS receivers, all-sky cameras, and particle detectors around the world to provide global measurements of ionospheric, magnetospheric and heliospheric phenomena. The small instrument programme is envisioned as a partnership between instrument providers, and instrument hosts in developing countries as one of United Nations Basic Space Science (UNBSS) activity. The lead scientist will provide the instruments (or fabrication plans for instruments) in the array; the host country will provide manpower, facilities, and operational support to obtain data with the instrument, located typically at a local university. This paper provides an overview of the IHY/UNBSS programme, its achievements and future plans.

The Virgo Cluster spiral NGC 4569 is known for its compact starburst in the core and unusual outflow of Hα emitting gas perpendicular to the galaxy disk. Recent radio polarimetric observations with the Effelsberg telescope reveal huge magnetized outflows. Preliminary results of our XMM-Newton observations uncover not only hot gas in the disk but also an extensive X-ray envelope around it. We investigate the possibility of starburst-induced galactic outflows in various gas phases and cluster influence on the galaxy evolution.

Recent observations with the Spitzer Space Telescope show clear evidence that star formation takes place in the surrounding of young massive O-type stars, which are shaping their environment due to their powerful radiation and stellar winds. In this work we investigate the effect of ionising radiation of massive stars on the ambient interstellar medium (ISM): In particular we want to examine whether the UV-radiation of O-type stars can lead to the observed pillar-like structures and can trigger star formation. We developed a new implementation, based on a parallel Smooth Particle Hydrodynamics code (called IVINE), that allows an efficient treatment of the effect of ionising radiation from massive stars on their turbulent gaseous environment. Here we present first results at very high resolution. We show that ionising radiation can trigger the collapse of an otherwise stable molecular cloud. The arising structures resemble observed structures (e.g. the pillars of creation in the Eagle Nebula, M16, or the Horsehead Nebula, B33). Including the effect of gravitation we find small regions that can be identified as formation places of individual stars. We conclude that ionising radiation from massive stars alone can trigger substantial star formation in molecular clouds.

We study the submillimetre (submm) properties of the following near-infrared (NIR)-selected massive galaxies at high redshifts: BzK-selected star-forming galaxies (BzKs), distant red galaxies (DRGs) and extremely red objects (EROs). We used the SCUBA HAlf Degree Extragalactic Survey (SHADES), the largest uniform submm survey to date. Since BzKs are expected to include obscured star-forming galaxies at 1.4 < z < 2.5, it is possible that the submm galaxies are a sub-group of BzKs. We identified 4 BzKs as submm galaxies within 93 arcmin2 by using high resolution radio images. This indicates that only ~20% of submm galaxies are BzKs. However, this fraction is consistent with the assumption that the most of submm galaxies at 1.4 < z < 2.5 are BzKs, considering the redshift distribution, radio-detection rate and observed K-band magnitudes of submm galaxies. We found no submm detections for EROs which are clearly non-BzKs. We identify two submm-bright NIR-selected galaxies, which satisfy all the selection criteria we adopt; i.e. they belong to the BzK-DRG-ERO overlapping population, or ‘extremely red’ BzKs. Although these extremely red BzKs are rare (0.25 arcmin−2), about 10% of this population could be submm galaxies. With a stacking analysis, we detected the 850-μm flux of submm-faint BzKs and EROs in our SCUBA maps. While the contribution from BzKs at z ~ 2 to submm background is about 10–15% and similar to that from EROs typically at z ~ 1, BzKs have a higher fraction (~30%) of submm flux in resolved sources than EROs and submm sources as a whole do. Therefore, submm flux of BzKs seems to be biased high. From the SED fitting using an evolutionary model of starbursts with radiative transfer, submm-bright BzKs are found to have the stellar mass of >5 × 1010M⊙ with the luminosity of >3 × 1012L⊙. From an average SED of submm-faint BzKs having similar B − z and z − K colours to submm-bright ones, we suggest that submm-bright BzKs are more massive than submm-faint ones.

The AMANDA neutrino telescope, prototype instrument of the IceCube neutrino observatory at South Pole, has collected data since 2000 in its final configuration. A period of 1001 days of livetime between 2000 and 2004 has been analysed in order to find evidence of a neutrino signal coming from point-like sources such as microquasars, active galactic nuclei, supernovae remnants or gamma ray bursts. A sensitivity to fluxes of νμ + νμ + ντ + ντ of dΦ/dE =1.0 · 10−10 (E/TeV)−2 · TeV−1 cm−2 s−1 was reached in the energy range between 1.6 TeV and 1.6 PeV. No significant excess over the background has been found so far. Flux upper limits infered from this study can constrain certain neutrino emission models of X-ray binaries. IceCube will have a substantially higher sensitivity. Currently at 10% of its final extension, it will comprise 4800 optical sensors deployed along 80 strings by early 2011, instrumenting one cubic kilometre volume of ice and 1 km2 at the surface.

We discuss prospects of using multi-dimensional time-dependent simulations to study the atmospheres of brown dwarfs and extrasolar giant planets, including the processes of convection, radiation, dust formation, and rotation. We argue that reasonably realistic simulations are feasible, however, separated into two classes of local and global models. Numerical challenges are related to potentially large dynamic ranges, and the treatment of scattering of radiation in multi-D geometries.

The true nature of the faint radio population remains elusive despite the many observations of the “sub-mJy” bump over the last two decades. This lack of information is largely due to the faint magnitudes of the optical counterparts to the radio sources. There are strong theoretical reasons (and a few observational ones) to believe that this rise in the counts is due to the emergence of a rapidly evolving star-forming population. Now, for the first time, we are able to separate the AGN and star-forming populations below 1mJy using a combination of multi-wavelength data from Spitzer, GMRT, MERLIN, CFHT, Keck, UKIRT, Subaru, Chandra and XMM-Newton. The many discriminators between these emission mechanisms include MIR colours, MIR/radio flux ratios, X-ray luminosities/spectra, optical spectra, radio morphologies and radio spectra. We can now derive the source counts separately for AGN and star-forming galaxies confirming that the latter population rise sharply at faint flux densities.

The study of the spatial distribution of interstellar extinction, AV, is important for many investigations of galactic and extragalactic objects. Three-dimensional (3D) extinction models have been produced using spectral and photometric stellar data, open cluster data, star counts, the Galactic dust distribution model.

Cycle lengths of active stars are derived from long-term photometric monitoring of their secular light variability. With the help of photographic data archives the lengths of the datasets are extended for HK Lac and V833 Tau. Using time-frequency analysis it is shown that the cycles are continuously changing in time. Thus, the reported cycle lengths derived by simple Fourier analysis are mean values that are valid only for a given time interval.

Star clusters are observed to form in a highly compact state and with low star-formation efficiencies, and only 10 per cent of all clusters appear to survive to middle- and old-dynamical age. If the residual gas is expelled on a dynamical time the clusters disrupt. Massive clusters may then feed a hot kinematical stellar component into their host-galaxy's field population thereby thickening galactic disks, a process that theories of galaxy formation and evolution need to accommodate. If the gas-evacuation time-scale depends on cluster mass, then a power-law embedded-cluster mass function may transform within a few dozen Myr to a mass function with a turnover near 105M, thereby possibly explaining this universal empirical feature. Discordant empirical evidence on the mass function of star clusters leads to the insight that the physical processes shaping early cluster evolution remain an issue of cutting-edge research.

GEMINI-S+CIRPASS configuration has been used to obtain 490 high quality spectra, centred in 1.3 microns of the NW-SE oriented, central 80 × 200 pc of NGC 5236 (M83), with spectral resolution of 3200. We determine the kinematics of this region with 0.36 arcsec sampling, sub-arcsec resolution. Disk-like motions are detected in Paβ at parsec scales around: a) the optical nucleus (ON), b) the dynamical centre of the CO velocity map (Sakamoto et al 2004) coincident with the K–band center (hereafter KC; Thatte et al. 2000), located 50 pc to the W of the optical nucleus, and c) the hidden condensation (hereafter HN; Mast et al. 2006), now more precisely located at 120 pc to the N-NW of the optical nucleus. The disk around ON has a radius of 10–15 pc and those around KC and HN can be traced approximately up to 40-50 pc from their kinematical centres. Rotation curve fittings using Satoh like spheroids give masses of 2–4×106M⊙, 10–15×106M⊙ and 15–20×106M⊙ respectively. N-body simulations using Gadget2 (Springel, 2005) show that ON, KC and HN will merge in 20-50 Myrs. A question that arise immediately is if this degree of dynamical activity is peculiar of M83 or it is a common behaviour, seen in this galaxy in all its dramaticity due to its small distance from us.

Large scale dynamo-generated fields are a combination of interlocked poloidal and toroidal fields. Such fields possess magnetic helicity that needs to be regenerated and destroyed during each cycle. A number of numerical experiments now suggests that stars may do this by shedding magnetic helicity. In addition to plain bulk motions, a favorite mechanism involves magnetic helicity flux along lines of constant rotation. We also know that the sun does shed the required amount of magnetic helicity mostly in the form of coronal mass ejections. Solar-like stars without cycles do not face such strong constraints imposed by magnetic helicity evolution and may not display coronal activity to that same extent. I discuss the evidence leading to this line of argument. In particular, I discuss simulations showing the generation of strong mean toroidal fields provided the outer boundary condition is left open so as to allow magnetic helicity to escape. Control experiments with closed boundaries do not produce strong mean fields.

In cold dark matter cosmological models, the first stars to form are believed to do so within small protogalaxies. We study the influence of low levels of metal enrichment on the cooling and collapse of ionized gas in these protogalactic halos using three-dimensional, smoothed particle hydrodynamics simulations.

Low mass X-ray binaries (LMXBs) offer us an unique opportunity to study the formation processes of compact objects. Secondary stars orbiting around either a black hole or a neutron star could have captured a significant amount of the ejected matter in the supernova explosions that most likely originated the compact objects. The detailed chemical analysis of these companions can provide valuable information on the parameters involved in the supernova explosion such us the mass cut, the amount of fall-back matter, possible mixing processes, and the energy and the symmetry of the explosion. In addition, this analysis can help us to find out the birth place of the binary system. We have measured element abundances of secondary stars in the LMXBs A0620–00, Cen X-4, XTE J1118+480 and Nova Sco 94. We find solar or above solar metalicity for all these systems, what appears to be independent on their locations with respect to the Galactic plane. A comparison of the observed abundances with yields from different supernova explosion together with the kinematic properties of these systems suggest a supernova origin for the compact objects in all of them except for A0620–00, for which a direct collapse cannot be discarded.