The pioneering observations of Spite & Spite showed lithium abundances in halo dwarfs to be almost uniform, irrespective of metallicity and mass over a range of effective temperatures from $\sim$5600 K up to the main-sequence turnoff. They inferred that the observed abundance was “hardly altered” from that produced in the hot Big Bang. Subsequent efforts have endeavoured to determine how small or large “hardly” could be. Simplistic arguments based on the uniformity of the Spite plateau suggest there should only be a small difference between the Big Bang lithium abundance and the observationally inferred plateau value, whereas more physical lines of reasoning suggest the difference could be more substantial. This review paper discusses observational and theoretical developments.

JPL continues to be active in creating ephemerides in support of spacecraft navigation as well as various other functions. Many of the products are available on web sites: (a) “Horizons”, the interactive web site, updated on an hourly basis, is located at http://ssd.jpl.nasa.gov. As of August, 2005, it contains orbital elements and ephemerides for the sun and 9 planets, 150 natural satellites (including the Moon), 291, 655 asteroids, 1631 comets, and 34 Spacecraft. Horizons uses the full precision of the JPL DE405.

(b)JPL's Planetary and Lunar Ephemerides in “export” format are available via FTP from the Internet: ftp://ssd.jpl.nasa.gov/pub/eph/export/ or on a CD-ROM: http://www.willbell.com/software/jpl.htm We advise to read the attached README.

(c)The observational data used in fitting the planetary ephemerides is available at the following web site, updated periodically: http://ssd.jpl.nasa.gov/plan-eph-data/

(d)SPICE Toolkit is a subroutine package for experienced programmers who write their own main driving programs for astrometrical computations. SPICE is available at http://naif.jpl.nasa.gov/. It contains a large library of subroutines useful in reading SPICE format ephemeris files (SPK) and in computing many solar system observation geometry parameters associated with the various JPL solar system missions. Available in Fortran, C, and IDL for most popular computing platforms.

We summarize the properties of Infrared Dark Clouds, massive, dense, and cool aggregations of interstellar gas and dust that are found throughout the Galaxy in projection against the strong mid-infrared background. We describe their distribution and give an overview of their physical properties and chemistry. These objects appear to be the progenitors of high-mass stars and star clusters, but seem to be largely devoid of star formation, which however is taking place in localized spots.

Several new multiply deuterated species have been detected over the past three years, including ND3 (van der Tak et al. 2002; Lis et al. 2002), CHD2OH, CD3OH (Parise et al. 2002, 2004), D2S (Vastel et al. 2003), HD2+ (Vastel et al. 2004) and D2CS (Marcelino et al. 2005). In addition, mono-deuterated species have been observed with abundances >10% of their un-deuterated analogues (e.g. CH2DOH observed by Parise et al. 2002; NH2D observed by Saito et al. 2000 and Hatchell 2003). These are remarkable results, given that the underlying abundance of deuterium in the local interstellar medium (ISM) is ∼10−5 times lower than that of hydrogen (Linsky 1998; Sonneborn et al. 2000).

Such large enhancements in the abundances of deuterium-bearing molecules can either be due to gas-phase or to grain-surface fractionation. Grain-surface reactions are undoubtedly important in producing saturated species such as methanol, water, ammonia, and hydrogen sulphide. Water ice is observed to be abundant and ubiquitous throughout the ISM, and enhanced abundances of gas-phase NH3, CH3OH, H2CO and H2S (among others) are observed in warmer regions around protostars where grain mantles have evaporated.

Recent observational and theoretical evidence suggests that the deuterium fractionation in star-forming regions is set by gas-phase and grain-surface reactions during the cold, dense pre-protostellar phase. For species which form on grain surfaces via H atom addition to CO, N, O and S, the deuterium fractionation on grains comes from the relative amounts of atomic D and H which are accreting from the gas. The observations of deuterated methanol and D2S require that the gas-phase atomic D/H ratio at the time the molecules formed was ≥ 0.1.

This paper presents results from chemical models of the prestellar core phase of star formation, showing how this high atomic D/H ratio can be produced, and discusses how models can also be used to look at deuterium fractionation in the protostellar stages of star formation.

The Deep Impact mission delivered 19 gigajoules of kinetic energy to the nucleus of comet 9P/Tempel 1 on 4 July 2005. Intensive observations, both from the two spacecraft and from Earth and Earth-orbit, while approaching the comet led to numerous new findings about comets. Observations of the impact event, from the flyby spacecraft have led us to a determination of numerous physical properties of the nucleus. Analysis of the near-IR spectra is still very preliminary.

This paper discusses several aspects of current research on high energy emission from supernova remnants, covering the following main topics: 1) The recent evidence for magnetic field amplification near supernova remnant shocks, which makes that cosmic rays are more efficiently accelerated than previously thought. 2) The evidence that ions and electrons in some remnants have very different temperatures, and only equilibrate through Coulomb interactions. 3) The evidence that the explosion that created Cas A was asymmetric, and seems to have involved a jet/counter jet structure. And finally, 4), I will argue that the unremarkable properties of supernova remnants associated with magnetar candidates, suggest that magnetars are not formed from rapidly ($P\approx 1$ ms) rotating proto-neutron stars. It is therefore more likely that they are formed from massive progenitor stars with high magnetic fields.

Cosmological numerical simulations suggest that dSphs and dEs formed hierarchically via assembling much smaller stellar/gas clumps. Star formation had occurred intensively during the building up phase that is shorter than ∼1 Gyr. Dark matter assembled hierarchically, while gas collapsed dissipatively; as a result the metallicity gradient was built up and stars at the galaxy centre tend to have larger rotational velocity and smaller velocity dispersion. There are increasing evidences, however, that suggest rather long-lasted star formation in dwarf galaxies with much smaller SFRs, with which cosmological simulations need to be reconciled.

We report preliminary results from our search for massive giant planets (6–12 Jupiter masses) around the known seven single white dwarfs in the Hyades cluster at sub-arcsec separations. At an age of 625 Myr, the white dwarfs had progenitor masses of about 3 solar masses, and massive gaseous giant planets should have formed in the massive circumstellar disks around these ex-Herbig A0 stars, probably at orbital separations similar or slightly larger than that of Jupiter. Such planets would have survived the post-Main-Sequence mass loss of the parent star and would have migrated outward adiabatically to orbital separations of about 25 AU. At the distance of the Hyades (45 pc) this corresponds to angular separations of about 0.5 arcsec which can be resolved with NICMOS/HST; the expected contrast in the J and H bands amount to 7.5 $\pm$ 1.5 mag.

Evaluation of our NICMOS data set did not reveal any evidence for planetary mass companions with masses down to about 10 Jupiter masses nor brown dwarfs around any of the seven white dwarfs for separations larger than 0.5 arcsec. However, we detected a low-mass, probably stellar, companion to a field white dwarf (WD1847-223J, distance $\sim$50 pc, age $\sim$1 Gyr; separation $\sim$0.5 arcsec, $\Delta$H $\sim$ 2.5 mag), using the NACO adaptive optics system at the VLT.

IAU Symposium 232 allows a snapshot of ELTs at a stage when design work in several critical mass projects has been seriously underway for two to three years. The status and some of the main initial design choices are reviewed for the North American Giant Magellan Telescope (GMT) and the Thirty Meter Telescope (TMT) projects and the European Euro-50 and the Overwhelmingly Large (OWL) projects. All the projects are drawing from the same “basket” of science requirements, although each project has somewhat different ambitions. The role of the project offices in creating the balance between project scope, timeline and cost, the “iron triangle” of project management, is emphasized with the OWL project providing a striking demonstration at this meeting. There is a reasonable case that the very broad range of science would be most efficiently undertaken on several complementary telescopes.

For a long time it has been usual to search for the objects that host the gas from which absorption line systems arise. However, the spatial distribution of metals around galaxies and more generally in the intergalactic medium is complex, and it is often very difficult to associate one absorption system with one galaxy. Except for possibly in the special case of DLA systems, it may be more appropriate to discuss the clustering properties of different classes of objects and to measure their correlation functions. I illustrate this approach with three examples: the distribution of metals around galaxies at intermediate redshift, the modelling of the clustering of C IV systems, and the determination of the transverse correlation function of the Lyman-$\alpha$ forest.

The ESO strategy for short listing ELT candidate sites is reviewed: it uses a specially designed tool to allow the simultaneous use of existing databases with various relevant parameters.

Using 138 low column density (N$_{\rm HI}=10^{12.5-16.5}$ cm$^{-2}$) Ly$\alpha$ “forest” absorbers discovered by HST at $z \leq 0.15$ and nearly one million low-$z$ galaxy redshifts from on-going surveys, we find that:

1. Although nearly 80% of Ly$\alpha$ forest absorbers are found within galaxy filaments, very few of them can be identified plausibly with bright ($\geq\,0.1\;{\rm L}^*$) galaxies. Either these absorbers are not related to any one individual galaxy or the individual galaxy to which they are related is fainter than $0.1\;{\rm L}^*$ (M$_B \geq -17$). O VI absorbers (H I+O VI) are found exclusively in galaxy filaments at median distances half as far away from the nearest galaxy as the Ly$\alpha$ absorber population from which they were selected (N$_{\rm HI}=10^{13.5-16.5}$ cm$^{-2}$).

2. Our work on individual absorber-galaxy associations at the lowest redshifts finds cases where low column density (N$_{\rm HI} = 10^{13.5-16.5}$ cm$^{-2}$) metal-enriched absorbers appear to be due to unbound winds from dwarf galaxies while higher column density (N$_{\rm HI}=10^{17.3-20}$ cm$^{-2}$) absorbers are found in the bound halos of massive galaxies. Therefore, both the statistics and a few well-studied examples lead us to propose that the low-$z$ IGM (and the Ly$\alpha$ forest absorbers in particular) are enriched in metals by outflowing winds from dwarf galaxies.

The presence of ices along the line of sight of high mass star forming regions is clearly evidenced by infrared observations. In dense molecular clouds icy grain mantles form after direct freeze out of gas phase species and after surface reactions of atoms and radicals on grains. Thus chemical composition of icy mantles differs from that of the gas phase. Due to the presence of the protostar and of cosmic radiation, icy mantles suffer from ion bombardment, UV photolysis and thermal annealing. Most of our knowledge on the physical and chemical properties of ices is based on the comparison between observations and laboratory experiments performed at low temperature (10-80 K). Experimental results show that after ion irradiation and UV photolysis the chemical composition and the structure of the sample is modified. Both more volatile and less volatile species are formed and if a C-bearing species is present in the original sample a refractory residue is left over after warm-up to room temperature. After thermal annealing, segregation, crystallization, and sublimation take place. Thus molecular species are released to the gas phase which could be enriched by species formed in the solid phase. Here I will discuss some recent laboratory experiments relevant to our knowledge of the physico-chemical properties of ices in star forming regions.

Dust particles in the solar system are produced from the small bodies: asteroids, comets, meteoroids and Kuiper belt objects. A further source of dust is provided by the warm interstellar medium that the Sun is currently embedded in and that streams into the solar system. We review the physical properties of solar system dust and trace back its interrelation with the small solar system bodies. Comets contain relatively pristine material that they transport to the inner solar system. The alteration of dust in the vicinity of comets is complex and connected to the gas evolution, but a significant part of the organic dust material survives these alterations. The optical properties of cometary dust are best described with a mixture of silicate and carbon bearing materials. As far as the darkness of the cometary material is concerned, according to recent models, this is not a result of the porosity, but rather of the darkness of the carbon bearing component. This does not contradict the observation of silicate features in the thermal emission brightness of cometary dust, since porous mixtures of silicate and carbon bearing dust can produce the observed polarization and albedo characteristics, as well as the silicate features. The carbon-bearing component is most likely an organic refactory component. The relative contributions of different sources change within the solar system dust cloud and depend as well on the measurement technique considered. In particular, the dust from asteroids, which provides a large component of the dust near Earth orbit, is also preferably seen with most of the detection methods. The majority of dust inward from 1 AU is produced from cometary dust and meteoroids. Dust material evaporation induced by collisions inward from 1 AU produces a minor heavy ion component in the solar wind plasma known as inner source pick-up ions.

We present VLT-FORS1 color–magnitude diagrams (CMDs) reaching the oldest main-sequence turnoffs for three fields at two galactocentric distances in the Fornax dSph galaxy. We derive the star formation history (SFH) for each field through comparison with synthetic CMDs and show that the main epoch of star formation has extended to more recent epochs toward the center of the galaxy. A small burst of star formation about 2 Gyr ago is a robust feature in the SFH of all fields. It might be related to the shell structure found in Fornax by Coleman et al. (2004), which in turn has been interpreted as the relic of a merger event that occurred in Fornax about 2 Gyr ago.

As we prepare to undertake the observational search for extrasolar terrestrial planets, theoretical modeling studies can help to prepare us for the likely diversity of the extrasolar terrestrial planets. This diversity may arise as a function of planetary system architecture and formation history, which results in a variety of initial planetary properties, as well as stellar, planetary and biological evolutionary processes. Modeling of the physical and chemical processes of the planetary environment, and their interaction with the parent star, allows us to understand the nature of the planetary characteristics that indicate habitability and life, and how these manifest in the planetary spectra. Here we present disk-averaged spectra of planets in our own solar system, and models of the Earth through several eons to understand the types of planetary characteristics that are likely to be observed by planned planet detection and characterization missions.

We have discovered a number of nonthermal X-ray features within central 40 pc region of the Galactic center by analysing 600-ksec observations of Chandra archival data. Most of the detected X-ray structures exhibit small-scale knot-like morphologies and their spectra are well reproduced by single hard power-law with photon indices of 1-2. Among them, the most outstanding features are the three X-ray knots which are aligned on a straight line from the potition of Sgr A* to north-northwest direction. The X-ray properties of these knots lead us to suspect that they are X-ray jets ejected from Sgr A* in the recent past. In addition, we have obtained an indication that the summed flux of nonthermal diffuse X-rays within 30 pc of the GC seems to be smoothly connected to the 20-100 keV flux detected with INTEGRAL IBIS/ISGRI. These results suggest that the origin of GC hard X-rays (or High energy Gamma-rays) is not (or partly) from the Galactic nucleus.

The orbital fits of multi-planetary systems from radial velocity data has proved to be a complex task. In some cases, different orbital solutions provide similarly good fits, especially when two planets are near mean-motion resonances. Ferraz-Mello et al (2005) and Goździewski et al (2005) showed that the published best fits of systems HD82932 and HD160691 are dynamically unstable, and re-determined their orbital parameters with Monte Carlo and genetic algorithms. In both cases dynamically stable orbits were found with RMS similar to the published orbits. It was also shown that uncertainties in the stellar mass Ferraz Mello et al (2005) and the stellar jitter Gozdziewski et al (2005) can significantly affect the orbital determination. Ford (2005) used a Markov chain Monte Carlo technique to quantify the orbit uncertainties. For some planetary systems he found a strong correlation between the orbital elements and/or significant non-Gaussian error distribution in the parameter space. As a consequence, the actual uncertainties in the orbital fits can be much larger (or smaller) than those published.

We present a coupled dynamical and chemical model for collapsing pre-stellar cores (Li et al. 2002; Shematovich et al. 2003a,b; Pavlyuchenkov et al. 2003). It treats the dynamics of thermally and magnetically supported cores in 1D, with an extended chemical network incorporated. The latest version of the model includes UV-irradiation of the core envelope. We have also developed a 2D Monte Carlo model of radiative transfer to compute molecular line profiles for comparison with observations.

The model allowed us to constrain evolutionary scenarios for collapsing pre-stellar cores, to calculate molecular line profiles from the spatial distribution of chemical species and the velocity field, and to characterize the chemical properties of dense cores.

We have determined line profiles along multiple lines of sight through a given pre-stellar core. This allowed us to compare model predictions with the observational maps of molecular lines available for L1544 and other well studied cores. The comparison of synthetic and observed line profile maps contributed to the understanding of the velocity field and pattern of chemical differentiation observed in individual cores.

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite Li plateau. We attribute this dispersion primarily to Li depletion (presumably due to extra mixing induced by stellar rotation) and to Galactic chemical evolution. We derive a primordial Li of 2.44$\,{\pm}\,$0.18 for A(Li)$_p$ = log N(Li/H) + 12.00. This agrees with the Li abundances predicted by the WMAP results. For stars cooler than the Li plateau we have evidence that Li depletion sets in at hotter temperatures for the higher metallicity stars than for the low-metal stars. This is the opposite sense of predictions from stellar models. The smooth transition of the Li content from the Li plateau stars to the cool stars adds weight to the inference of Li depletion in the plateau stars.